LUBRICANT FOR MARINE ENGINE
The present invention is applicable to the field of lubricants, and more
particularly to the field of lubricants for marine engines, in particular for two-stroke
marine engines. More particularly, the present invention relates to a lubricant for
marine engines comprising at least one base oil, at least one overbased detergent,
at least one neutral detergent and at least one fatty amine. The lubricant according
to the invention can be used both with fuel oils with a high sulphur content and fuel
oils with a low sulphur content. The lubricant according to the invention has sufficient
neutralizing power vis-a-vis sulphuric acid formed during the combustion of fuel oils
with a high sulphur content, while limiting the formation of deposits during the use of
fuel oils with a low sulphur content.
The lubricant according to the invention more particularly makes it possible to
prevent corrosion and/or reduce the formation of insoluble metallic salt deposits in
two-stroke marine engines during the combustion of any type of fuel oils, i.e. with a
high and with a low sulphur content.
The lubricant according to the invention also has good properties of thermal
resistance and cleanliness of the piston-cylinder assembly.
The present invention also relates to a method for lubricating a marine engine, and
more particularly a two-stroke marine engine that can be used both with fuel oils with
a high sulphur content and fuel oils with a low sulphur content utilizing this lubricant.
The present invention also relates to a composition of the additive-concentrate type
comprising at least one fatty amine.
The marine oils used in slow-speed two-stroke crosshead engines are of two types:
cylinder oils on the one hand, ensuring the lubrication of the piston-cylinder
assembly, and system oils on the other hand, ensuring the lubrication of all the
moving parts other than those of the piston-cylinder assembly. Within the pistoncylinder
assembly, the combustion residues containing acid gases are in contact
with the lubricant oil.
The acid gases are formed during the combustion of the fuel oils; these are in
particular sulphur oxides (SO2, SO,), which are then hydrolysed during contact with
the humidity present in the combustion gases and/or in the oil. This hydrolysis
generates sulphurous acid (HSO,) or sulphuric acid (H2SO4).
In order to preserve the surface of the liners and prevent excessive corrosive wear,
these acids have to be neutralized, which is generally carried out by reaction with the
basic sites included in the lubricant.
The neutralizing capacity of an oil is measured by its BN or Base Number, which
5 characterizes its basicity. It is measured according to the standard ASTM D-2896
and is expressed in equivalents by weight of potash per gram of oil or mg of KOHlg
of oil. The BN is a standard criterion making it possible to adjust the basicity of the
cylinder oils to the sulphur content of the fuel oil used, in order to be able to
neutralize all of the sulphur contained in the fuel, and capable of being converted to
10 sulphuric acid by combustion and hydrolysis.
Thus, the higher the sulphur content of a fuel oil, the higher the BN of a marine oil
must be. This is why marine oils with BNs varying from 5 to 100 mg KOHlg of oil are
available on the market. This basicity is provided by detergents which are overbased
with insoluble metallic salts, in particular metallic carbonates. The detergents, mainly
fi5 of the anionic type, are for example metallic soaps of the salicylate, phenate,
sulphonate, carboxylate type, etc. which form micelles where the insoluble metallic
salt particles are maintained in suspension. The usual overbased detergents
intrinsically have a BN conventionally comprised between 150 and 700 mg of potash
per gram of detergent. Their content by mass in the lubricant is determined as a
20 function of the level of BN to be achieved.
A part of the BN can also be provided by non-overbased or "neutral" detergents with
a BN typically less than 150 mg of potash per gram of detergent. However, it is not
possible to envisage producing cylinder lubricant formulas for marine engines, in
particular for two-stroke marine engines, where the entire BN is provided by "neutral"
25 detergents: it would in fact be necessary to incorporate them in excessive quantities,
which could be detrimental to the efficiency of the lubricant and would not be realistic
from an economic point of view.
The insoluble metallic salts of the overbased detergents, for example calcium
carbonate, therefore contribute significantly to the BN of the usual lubricants. It can
30 be considered that approximately at least 50%, typically 75%, of the B.N of the
cylinder lubricants is thus provided by these insoluble salts.
The actual detergent part, or metallic soaps, found in both the neutral and overbased
detergents, typically provides most of the remainder of the BN.
Environmental concerns have led, in certain areas and in particular coastal areas, to
35 requirements relating to the limitation of the levels of sulphur in the fuel oils used on
ships.
Thus, the MARPOL Annex 6 regulations (Regulations for the Prevention of Air
Pollution from Ships) issued by the IMO (International Maritime Organization)
entered into force in May 2005. It sets a maximum sulphur content of 4.5% by weight
with respect to the total weight of the fuel oil for heavy fuel oils as well as creating
5 sulphur oxide emission control areas, called SECAs (SOX Emission Control Areas).
By heavy fuel oils is meant high-viscosity fuels mainly used for large diesel engines
installed on board ships.
Thus, ships entering these areas must use fuel oils with a maximum sulphur content
of 1.5% by weight with respect to the total weight of the fuel oil or any other
10 alternative treatment aimed at limiting SOX emissions in order to comply with the
specified values.
More recently, amendments have been made to the MARPOL Annexe 6
Regulations. These amendments are summarized in the table below. Thus, the
restrictions on the maximum sulphur content have become more severe with a
15 worldwide maximum content reduced from 4.5% by weight with respect to the total
weight of the fuel oil to 3.5% by weight with respect to the total weight of the fuel oil.
The SECAs (Sulphur Emission Control Areas) have become ECAs (Emission
Control Areas) with an additional reduction in the maximum permissible sulphur
content from 1.5% by weight with respect to the total weight of the fuel oil to 1 .O% by
20 weight with respect to the total weight of the fuel oil and the addition of new limits
relating to contents of NOx and particles.
Amendments to MARPOL Annex 6
(MEPC Meeting No. 57 - April 2008)
General limit Limit for the ECAs
3.5% by weight with 1 % by weight with respect
respect to the total to the total weight Maximum sulphur content weight of the fuel oil on of the
01/01/2012 fuel oil on 01/07/2010
0.5% by weight with 0.1 % by weight with
respect to the total respect to the total weight
weight of the fuel oil on of the fuel oil on
01/01/2020 01/01/2015
Ships sailing trans-continental routes use several types of heavy fuel oil depending
on local environmental constraints whilst making it possible for them to optimize their
25 operating costs. This situation will continue whatever the final level of the maximum
sulphur content permissible in fuel oils.
Thus many container ships are utilizing several bunker tanks, for a fuel oil with a
high sulphur content (at most 3.5% by weight of sulphur with respect to the total
weight of the fuel oil and above) or "high seas" fuel oil on the one hand, and for an
"ECA fuel oil with a sulphur content of less than or equal to 1% by weight with
respect to the total weight of the fuel oil on the other hand.
Changing between these two categories of fuel oil can require adaptation of the
5 engine's operating conditions, in particular the utilization of appropriate cylinder
lubricants.
At present, in the presence of fuel oil with a high sulphur content (3% by weight with
respect to the total weight of the fuel oil and above), marine lubricants having a BN
of the order of 70 mg of KOHImg of lubricant are mainly used
10 In the presence of a fuel oil with a low sulphur content (1% by weight with respect to
the total weight of the fuel oil and below), marine lubricants having a BN of the order
of 40 mg of KOHImg of lubricant are mainly recommended.
In both these cases, a sufficient neutralizing capacity is then achieved as the
necessary concentration at basic sites provided by the overbased detergents of the
15 marine lubricant is reached, but it is necessary to change lubricant each time the
type of fuel oil is changed.
Furthermore, each of these lubricants has limits of use for the following reasons: the
use of a cylinder lubricant with a BN of 70 mg of KOHIg of lubricant in the presence
of a fuel oil with a low sulphur content (1% by weight with respect to the total weight
20 of the fuel oil and below) and a fixed level of lubrication, creates a significant excess
of basic sites and a risk of destabilization of the unused overbased detergent
micelles, which contain insoluble metallic salts. This destabilization results in the
formation of deposits of insoluble metallic salts (for example calcium carbonate)
having a high degree of hardness, mainly on the piston crown, and can in the long
25 term lead to a risk of excessive wear of a piston-liner polishing type. As for the use of
a cylinder lubricant of BN 40 mg of KOHIg of lubricant, such a BN does not provide
the lubricant with sufficient neutralizing capacity and can thus lead to a significant
risk of corrosion.
30 Thus, the optimization of the cylinder lubrication of a two-stroke engine then requires
the selection of a lubricant the BN of which is suited to the sulphur content of the fuel
oil used and to the engine's operating conditions. This optimization reduces the
flexibility of operation of the engine and requires significant technical skill on the part
of the crew in defining the conditions under which the change from one type of
35 lubricant to the other must be carried out.
In order to simplify operations, it would therefore be desirable to have a single
cylinder lubricant, in particular for two-stroke marine engines, that can be used both
with high-sulphur fuel oils and with low-sulphur fuel oils.
In particular, a need exists for formulations in which the BN is provided in an
alternative way to the overbased detergents, by compounds that do not give rise to
metallic deposits when they are present in excess relative to the quantity of sulphuric
acid to be neutralized.
Several solutions have been proposed in order to meet this need.
Document WO 20091153453 describes a cylinder lubricant for two-stroke marine
engines that can be used both with fuel oils with a high sulphur content and fuel oils
with a low sulphur content and comprising at least one overbased detergent and at
least one oil-soluble fatty amine.
However, in this lubricant, the presence of a neutral detergent is optional.
Furthermore, in this lubricant, the percentage by mass of overbased detergents with
respect to the total weight of the lubricant is selected so that the BN provided by the
metallic carbonate salts represents a contribution of at most 20 milligrams of potash
per gram of lubricant to the total BN of the lubricant. Moreover, the fatty amines
exemplified in this document and making it possible to improve the neutralization
efficiency correspond to fatty mono- or di-amines.
Document WO 20121140215 describes a cylinder lubricant for two-stroke marine
engines that can be used both with fuel oils with a high sulphur content and fuel oils
with a low sulphur content and comprising at least one overbased detergent, at least
one neutral detergent and at least one alkoxylated fatty amine.
However, the alkoxylated fatty amines exemplified in this document and making it
possible to improve the neutralization efficiency correspond to alkoxylated fatty
monoamines.
Moreover,'the BN of the lubricant described in this document cannot be too high,
and in particular cannot be greater than 55 mg of KOHlmg of lubricant.
In addition to the constraints of neutralization efficiency vis-a-vis fuel oils with a high
sulphur content and with a low sulphur content, increased thermal. resistance
requirements for the lubricant, and therefore cleanliness of the ring-piston-cylinder
zone (or RPC zone) are to be taken into account.
It would thus be desirable to have available a cylinder lubricant for marine engines,
in particular for two-stroke marine engines, that can be used both with fuel oils with a
high sulphur content and fuel oils with a low sulphur content and making it possible
to have both a high BN, in particular of at least 50 mg KOHlg of cylinder lubricant,
and a good neutralizing capacity, while having good thermal resistance and thus
good cleanliness of the engine, and in particular of the piston-cylinder assembly.
It would also be desirable to have available a cylinder lubricant for marine engines,
in particular for two-stroke marine engines, presenting little or no risk of thickening
over time, and in particular during use.
5 Description of the invention
An objective of the present invention is to provide a cylinder lubricant overcoming
some or all of the abovementioned drawbacks.
Another objective of the present invention is to provide a cylinder lubricant that is
10 resistant to ageing and retains its properties over time.
Another objective of the invention is to provide a cylinder lubricant the formulation of
which is easy to implement.
Another objective of the present invention is to provide a method for lubricating a
marine engine, and more particularly a two-stroke marine engine that can be used
15 both with fuel oils with a high sulphur content and fuel oils with a low sulphur content.
The present invention relates to a cylinder lubricant having a BN that is sufficiently
high to efficiently neutralize sulphuric acid formed during the use of fuel oils with a
high sulphur content, a significant part of said BN being provided by oil-soluble
20 species which do not give rise to metallic deposits when they are partially consumed
during the use of fuel oils with a low s.ulphur content.
The present invention therefore relates to a cylinder lubricant having a BN
determined according to the standard ASTM D-2896 greater than or equal to 50
25 milligrams of potash per gram of lubricant, comprising:
at least one lubricant base oil,
at least one detergent based on alkali or alkaline-earth metals, overbased with
metallic carbonate salts,
at least one neutral detergent,
3 0 a mixture of fatty amines comprising at least one fatty amine of formula (I):
RI-[NR~(CH~)~I~-NH~
(1)
in which:
3 5 R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH2)20H group,
the content by weight of fatty amine of formula (I) being greater than or equal
to 90% with respect to the total weight of the mixture of fatty amines,
the fatty amine having a BN determined according to the standard ASTM D-
2896 ranging from 150 to 600 milligrams of potash per gram of amine,
5 the percentage by mass of fatty amine with respect to the total weight of the
lubricant being selected so that the BN provided by this compound
represents a contribution of at least 10 milligrams of potash per gram of
lubricant to the total BN of said cylinder lubricant and,
the percentage by mass of the overbased detergent with respect to the total
10 weight of the lubricant being selected so that the BN provided by the metallic
carbonate salts represents a contribution of at least 20 milligrams of potash
per gram of lubricant to the total BN of said cylinder lubricant.
The applicant has found that it was possible to formulate cylinder lubricants where a
15 significant part of the BN is provided by fatty amines that are soluble in the lubricant
base oil, while maintaining the level of performance with respect to standard
formulations with an equivalent or even greater BN.
The performances in question here are in particular the capacity to neutralize
sulphuric acid, measured using the enthalpy test described hereafter, as well as
20 thermal resistance, measured using the ECBT test also described hereafter.
The cylinder lubricant according to the invention thus has such performances, while
retaining a viscosity which makes it suitable for its use.
However it is not possible to completely dispense with the provision of BN by the
25 insoluble metallic particles of the overbased detergents: in fact they constitute the
"ultimate reserve" of basicity that is indispensable when operating with fuel oils with
a high sulphur content, for example greater than 3% by weight with respect to the
total weight of the fuel oil.
These insoluble metallic salts also have a favourable anti-wear effect as long as
30 they are maintained dispersed in the lubricant in the form of stable micelles.
The applicant has also surprisingly found that in the presence of a significant
provision of BN by said fatty amines, and despite a significant provision, i.e. of at
least 20 mg of potash per gram of lubricant, of BN by the insoluble metallic salts of
the overbased detergents, typically the metallic carbonates, the cylinder lubricant
35 retains a good neutralizing capacity and good thermal resistance.
Thus, the present invention makes it possible to formulate cylinder lubricants for
marine engines, in particular for two-stroke marine engines, allowing them to be
useable both with fuel oils with a high sulphur content and fuel oils with a low
sulphur content and allowing them at the same time to have a high BN while
maintaining the other performances of the lubricant.
Advantageously, the cylinder lubricants according to the invention have a good
sulphuric acid neutralizing capacity.
Advantageously, the cylinder lubricants according to the invention have a good
thermal resistance.
Advantageously, the cylinder lubricants according to the invention retain a good
viscosity stability over time.
Advantageously, the cylinder lubricants according to the invention present little or no
risk of thickening as a function of the conditions of use.
In an embodiment, the cylinder lubricant according to the invention contains no fatty
amines other than fatty amines corresponding to formula (I).
Thus, the cylinder lubricant according to the invention can comprise one or more
fatty amines of formula (I) but contains no fatty amines other than the fatty amine or
amines of formula (I).
In an embodiment, the invention relates to a cylinder lubricant having a BN
determined according to the standard ASTM D-2896 greater than or equal to 50
milligrams of potash per gram of lubricant, comprising:
at least one lubricant base oil,
0 at least one detergent based on alkali or alkaline-earth metals, overbased with
metallic carbonate salts,
at least one neutral detergent,
at least one primary, secondary or tqrtiary fatty monoalcohol, the alkyl chain of
which is linear or branched, saturated or unsaturated and comprising at least
12 carbon atoms, preferentially from 12 to 24 carbon atoms, more
preferentially from 16 to 18 carbon atoms, advantageously the primary
monoalcohols with a saturated, linear alkyl chain,
a mixture of fatty amines comprising at least one fatty amine of formula (I):
RI-[NRz(CHZ)~I~-NHZ
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH2)20H group,
the content by weight of fatty amine of formula (I) being greater than or equal
to 90% with respect to the total weight of the mixture of fatty amines,
the fatty amine having a BN determined according to the standard ASTM D-
2896 ranging from 150 to 600 milligrams of potash per gram of amine,
the percentage by mass of fatty amine with respect to the total weight of the
lubricant being selected so that the BN provided by this compound
10 represents a contribution of at least 10 milligrams of potash per gram of
lubricant to the total BN of said cylinder lubricant and,
the percentage by mass of overbased detergent with respect to the total
weight of the lubricant being selected so that the BN provided by the metallic
carbonate salts represents a contribution of at least 20 milligrams of potash
15 per gram of lubricant to the total BN of said cylinder lubricant.
In an embodiment, the cylinder lubricant essentially consists of:
at least one lubricant base oil,
at least one detergent based on alkali or alkaline-earth metals, overbased with
20 metallic carbonate salts,
at least one neutral detergent,
a mixture of fatty amines comprising at least one fatty amine of formula (I):
RI-[NRZ(CHZ)~I~-NHZ
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CHZ)~OHg roup,
the,content by weight of fatty amine of formula (I) being greater than or equal
to 90% with respect to the total weight of the mixture of fatty amines,
the fatty amine having a BN determined according to the standard ASTM D-
2896 ranging from 150 to 600 milligrams of potash per gram of amine,
the percentage by mass of fatty amine with respect to the total weight of the
lubricant being selected so that the BN provided by this compound
represents a contribution of at least 10 milligrams of potash per gram of
lubricant to the total BN of said cylinder lubricant and,
the percentage by mass of overbased detergent with respect to the total
weight of the lubricant being selected so that the BN provided by the metallic
carbonate salts represents a contribution of at least 20 milligrams of potash
per gram of lubricant to the total BN of said cylinder lubricant.
5
In an embodiment, the cylinder lubricant essentially consists of:
at least one lubricant base oil,
at least one detergent based on alkali or alkaline-earth metals, overbased with
metallic carbonate salts,
10 at least one neutral detergent,
at least one primary, secondary or tertiary fatty monoalcohol, the alkyl chain of
which is linear or branched, saturated or unsaturated and comprising at least
12 carbon atoms, preferentially from 12 to 24 carbon atoms, more
preferentially from 16 to 1.8 carbon atoms, advantageously the primary
15 monoalcohols with a saturated, linear alkyl chain,
a mixture of fatty amines comprising at least one fatty amine of formula (I):
RI-[NRz(CHZ)~I~-NHZ
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH,),OH group,
the content by weight of fatty amine of formula (I) being greater than or equal
to 90% with respect to the total weight of the mixture of fatty amines,
25 the fatty amine having a BN determined according to the standard ASTM D-
2896 ranging from 150 to 600 milligrams of potash per gram of amine,
the percentage by mass of fatty amine with respect to the total weight of the
lubricant being selected so that the BN provided by this compound
represents a contribution of at least 10 milligrams of potash per gram of
30 lubricant to the total BN of said cylinder lubricant and,
the percentage by mass of overbased detergent with respect to the total
weight of the lubricant being selected so that the BN provided by the metallic
carbonate salts represents a contribution of at least 20 milligrams of potash
per gram of lubricant to the total BN of said cylinder lubricant.
35
The invention also relates to the use of a cylinder lubricant as defined above for
lubricating a two-stroke marine engine.
The invention also relates to the use of a cylinder lubricant as defined above as a
single cylinder lubricant that can be used both with fuel oils with a sulphur content of
less than 1% by weight with respect to the total weight of the fuel oil, with fuel oils
with a sulphur content ranging from 1 to 3.5% by weight with respect to the total
5 weight of the fuel oil and with fuel oils with a sulphur content greater than 3.5% by
weight with respect to the total weight of the fuel oil.
In an embodiment, the cylinder lubricant as defined above is used as a single
cylinder lubricant that can be used both with fuel oils with a sulphur content of less
10 than 1% by weight with respect to the total weight of the fuel oil and with fuel oils
with a sulphur content ranging from 1 to 3.5% by weight with respect to the total
weight of the fuel oil.
The invention also relates to the use of a cylinder lubricant as defined above in order
15 to prevent corrosion and/or reduce the formation of insoluble metallic salt deposits in
the two-stroke marine engines during the combustion of any type of fuel oil the
sulphur content of which is less than 3.5% by weight with resped to the total weight
of the fuel oil.
20 The invention also relates to an additive concentrate, for the preparation of cylinder
lubricant having a BN determined according to the standard ASTM D-2896 greater
than or equal to 50 milligrams of potash per gram of lubricant, said concentrate
having a BN ranging from 100 to 400 mg of potash per gram of concentrate, and
comprising at least one detergent based on alkali or alkaline-earth 'metals,
25 overbased with metallic carbonate salts, at least one neutral detergent and at least
one fatty amine having a BN ranging from 150 to 600 mg of potashlg of amine
according to the standard ASTM D-2896 and of formula (I):
Rl-[NR~(cH2)313-NH2
(1)
3 0 in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH2)20H group,
.35 the percentage by mass of said fatty amine in the concentrate being selected
so as to provide said concentrate with a contribution of BN determined
according to the standard ASTM D-2896 ranging from 20 to 300 milligrams of
potash per gram of concentrate.
The invention also relates to a method for lubricating a two-stroke marine engine .$
comprising at least one step of bringing the engine into contact with a cylinder . $1 I)
k
lubricant as defined above or obtained from the additive concentrate as described 4; P
5 previously. +22!
*
6:
The invention also relates to a method for preventing corrosion andlor reducing the %?. $.I4"
Q formation of insoluble metallic salt deposits in two-stroke marine engines during the .$ -7 3 combustion of any type of fuel oil the sulphur content of which is less than 3.5% by ,Z
j
10 weight with respect to the total weight of the fuel oil, comprising at least one step of 3 tct
bringing the engine into contact with a cylinder lubricant as defined above or
obtained from the additive concentrate as described previously.
r i
Detailed description of the invention I
-6
15 The percentages indicated below correspond to percentages by mass of active A z7 .$
ingredient.
Fatty amines
.$ 4
20 The cylinder lubricant according to the invention comprises a mixture of fatty amines r
comprising at least one fatty amine of formula (I):
Rl-[NR2(CH2)313-NH2
(1)
in which:
25 R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH2),0H group,
the content by weight of fatty amine of formula (I) being greater than or equal to 90%
with respect to the total weight of the mixture of fatty amines,
30 the fatty amine having a BN determined according to the standard ASTM D-2896
ranging from 150 to 600 milligrams of potash per gram of amine.
By fatty amine, is meant the fatty amine of formula (I).
By mixture of fatty amines, is meant a mixture of fatty amines at least one fatty
35 amine of which is a fatty amine of formula (I).
In an embodiment of the invention, the BN of the fatty amine determined according
to the standard ASTM D-2896 can range from 250 to 600 milligrams of potash per
gram of amin'e, preferably from 300 to 500 milligrams of potash per gram of amine.
In another embodiment, the BN of the mixture of fatty amines determined according
5 to the standard ASTM D-2896 can range from 250 to 600 milligrams of potash per
gram of amine, preferably from 300 to 500 milligrams of potash per gram of amines.
The fatty amines are mainly obtained from carboxylic acids.
The starting fatty acids for obtaining fatty amines according to the invention can be
. 10 selected from the myristic, pentadecylic, palmitic, margaric, stearic, nonadecylic,
arachidic, heneicosanoic, behenic, tricosanoic, lignoceric, pentacosanoic, cerotic,
heptacosanoic, montanic, nonacosanoic, melissic, hentriacontanoic, laceroic acids or
from the unsaturated fatty acids such as palmitoleic, oleic, erucic, nervonic, linoleic, alinolenic,
gamma-linolenic, di-homo-gamma-linolenic, arachidonic, eicosapentaenoic,
15 docosahexaenoic acid.
Thec preferred fatty acids can have originated from the hydrolysis of the triglycerides
present in vegetable and animal oils, such as coconut, palm, olive, peanut,
rapeseed, sunflower, soya, cotton, linseed oil, beef tallow, etc..
20 The natural oils can have been genetically modified so as to enrich their content of
certain fatty acids. By way of example, rapeseed oil or oleic sunflower oil may be
mentioned.
In an embodiment, the fatty amines used in the lubricants according to the invention
25 can be obtained from natural, vegetable or animal resources.
In an embodiment of the invention, the mixture of fatty amines comprises at least
one fatty amine of formula (I) in which R1 represents a linear or branched, saturated
or unsaturated alkyl group comprising from 14 to 22 carbon atoms, preferably from
30 16 to 20 carbon atoms.
In another embodiment of the invention, the mixture of fatty amines comprises at
least one fatty amine of formula (I) in which R2 represents a hydrogen atom.
35 In another preferred embodiment of the invention, the mixture of fatty amines
comprises at least one fatty amine of formula (I) in which:
- R1 represents a linear or branched, saturated or unsaturated alkyl group
comprising from 14 to 22 carbon atoms, preferably from 16 to 20 carbon
atoms, and
- R2 represents a hydrogen atom.
5
In another preferred embodiment of the invention, the mixture of fatty amines is
presented in the form:
- of at least one fatty amine of formula (I) in which Rl represents a linear or
branched, saturated or unsaturated alkyl group comprising from 14 to 16
10 carbon atoms and R2 represents a hydrogen atom,
- of at least one fatty amine of formula (I) in which Rl represents a linear or
branched, saturated or unsaturated alkyl group comprising at least 18
carbon atoms and R2 represents a hydrogen atom,
and
15 - of at least one fatty amine of formula (I) in which R1 represents a linear or
branched, saturated or unsaturated alkyl group comprising at least 20
carbon atoms and R2 represents a hydrogen atom.
In a more preferred embodiment of the invention, the mixture of fatty amines is
presented in the form:
- of at least one fatty amine of formula (I) in which Rl represents a linear or
branched, saturated or unsaturated alkyl group comprising from 14 to 16
carbon atoms and R2 represents a hydrogen atom,
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched, saturated or unsaturated alkyl group comprising
at least 18 carbon atoms and R2 represents a hydrogen atom,
and
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched, saturated or unsaturated alkyl group comprising at least 20
carbon atoms and R2 represents a hydrogen atom,
t h e sum of the content by weight of said fatty amines of formula (I) being
greater than or equal to 90% and strictly less than 100% with respect to the
weight of said mixture of fatty amines.
35 In another preferred embodiment of the invention, the mixture of fatty amines is
presented in the form:
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched unsaturated alkyl group comprising from I 6 to 20 carbon atoms,
preferably from 18 to 20 carbon atoms and R2 represents a hydrogen
atom, and
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched saturated alkyl group comprising from 16 to 20 carbon atoms,
5 preferably from 18 to 20 carbon atoms and R2 represents a hydrogen
atom.
In a more preferred embodiment of the invention, the mixture of fatty amines is
presented in the form:
10 - of at least one fatty amine of formula (I) in which R1 represents a linear or
branched unsaturated alkyl group comprising from 16 to 20 carbon atoms,
preferably from 18 to 20 carbon atoms and R2 represents a hydrogen
atom,
- of at least one fatty amine of formula (I) in which R1 represents a linear or
15 branched saturated alkyl group comprising from 16 to 20 carbon atoms,
preferably from 18 to 20 carbon atoms and R2 represents a hydrogen
atom,
the sum of the content by weight of said fatty amines of formula (I) being
greater than or equal to 90% and strictly less than 100% with respect to the
20 weight of said mixture of fatty amines.
The products Tetrameen OV and Tetrameen T marketed by the company Akzo
Nobel may be mentioned as examples of mixtures of fatty amines according to the
invention.
25
The percentage by mass of fatty amine with respect to the total weight of the
cylinder lubricant according to the invention is selected so that the BN provided by
this compound represents a contribution of at least 10 milligrams of potash per gram
of lubricant to the total BN of said cylinder lubricant
3 0
The part of BN provided by a fatty amine in the cylinder lubricant according to the
invention (in milligrams of potash per gram of finished lubricant, or BN "points1') is
calculated from its intrinsic BN measured according to the standard ASTM D-2896
and its percentage by mass in the finished lubricant:
3 5 amine BN lub = x. amine BNI100
amine BN lub = contribution of the amine to the BN of the finished lubricant
x = % by mass of the amine in the finished lubricant
amine BN = intrinsic BN of the amine alone (ASTM D-2896).
In an embodiment of the invention, the percentage by mass of fatty amine with
respect to the total weight of the cylinder lubricant is selected so that the BN
provided by this compound represents a contribution of 10 to 60 milligrams of
potash per gram of lubricant, more preferentially from 10 to 30 milligrams of potash
5 per gram of lubricant, to the total BN of said cylinder lubricant.
In another embodiment of the invention, the percentage by mass of fatty amine with
respect to the total weight of the cylinder lubricant is selected so that the BN
provided by this compound represents at least lo%, preferably 10 to 50%, more
10 preferentially 10 to 30% of the total BN of said cylinder lubricant.
In another embodiment of the invention, the percentage by mass of the mixture of
fatty amines with respect to the total weight of cylinder lubricant ranges from 2 to
10%.
15 In another embodiment of the invention, the percentage by mass of the mixture of
fatty amines with respect to the total weight of cylinder lubricant ranges from 2 to
6%.
In a preferred embodiment, the cylinder lubricant according to the invention contains
20 no fatty amines other than fatty amines corresponding to formula (I).
In another embodiment of the invention, the cylinder lubricant can comprise at least
one other additional fatty amine different from the fatty amines corresponding to
formula (I).
. 25 The additional fatty amine can be selected from the monoamines, the diamines, the
fatty triamines, non-alkoxylated or alkoxylated.
In a preferred embodiment of the invention, the content by weight of fatty amine of
formula (I) is strictly less than 100% with respect to the total weight of the mixture of
30 fatty amines.
In a preferred embodiment of the invention, the content by weight of fatty amine of
formula (I) ranges from 90 to 99.9% with respect to the total weight of the mixture of
fatty amines.
35
Overbased or neutral detergents
..:\f !
. i.!
P i
The cylinder lubricant according to the invention comprises at least one detergent
based on alkali or alkaline-earth metals, overbased with metallic carbonate salts and
at least one neutral detergent, the percentage by mass of the overbased detergent
with respect to the total weight of the lubricant being selected so that the BN
5 provided by the metallic carbonate salts represents a contribution of at least 20
milligrams of potash per gram of lubricant to the total BN of said cylinder lubricant.
,The detergents used in the cylinder lubricants according to the present invention are
well known to a person skilled in the art.
10 .The detergents commonly used in the formulation of lubricants are typically anionic
compounds comprising a long lipophilic hydrocarbon-containing chain and a
hydrophilic head. The associated cation is typically a metallic cation of an alkali or
alkaline-earth metal.
The detergents are preferentially selected from the salts of alkali or alkaline-earth
15 metals of carboxylic acids, sulphonates, salicylates, naphthenates, as well as the
salts of phenates.
The alkali and alkaline-earth metals are preferentially calcium, magnesium, sodium
or barium.
These metallic salts can contain the metal in an approximately stoichiometric
20 quantity with respect to the anionic group(s) of the detergent. In this case, the term
non-overbased or "neutral" detergents is used, although they also provide a certain
basicity. These "neutral" detergents typically have a BN, measured according to
ASTM D2896, less than 150 mg KOHIg, or less than 100 mg KOHIg, or even less
than 80 mg KOHIg of detergent.
. .
25 This type of detergents referred to as neutral can partially contribute to the BN of the
cylinder lubricants according to the present invention. For example neutral
detergents of the following types: carboxylates, sulphonates, salicylates, phenates,
naphthenates of alkali and alkaline-earth metals, for example of calcium, sodium,
magnesium, barium will be used.
30 When the metal is in excess (in a quantity greater than the stoichiometric quantity
with respect to the anionic group(s) of the detergent), we are dealing with detergents
referred to as overbased. Their BN is high, greater than 150 mg KOHIg of detergent,
typically ranging from 200 to 700 mg KOHIg of detergent, preferentially from 250 to
450 mg KOHIg of detergent.
'
The metal in excess providing the detergent with its overbased character is
presented in the form of metallic salts that are insoluble in oil, for example 8
t
carbonate, hydroxide, oxalate, acetate, glutamate, preferentially carbonate. I < @ dl
1 In one and the same overbased detergent, the metals of these insoluble salts can
be the same as those of the oil-soluble detergents or be different. They are
preferentially selected from calcium, magnesium, sodium or barium.
The overbased detergents are thus presented in the form of micelles composed of
.insoluble metallic salts maintained in suspension in the cylinder lubricant by the
detergents in the form of oil-soluble metallic salts.
These micelles can contain one or more types of insoluble metallic salts, stabilized
by one or more types of detergent.
The overbased detergents comprising a single type of detergent-soluble metallic salt
are generally named after the nature of the hydrophobic chain of the latter
detergent.
15 Thus, they are referred to as being of the phenate, salicylate, sulphonate,
naphthenate type according to whether this detergent is a phenate, salicylate,
sulphonate, or naphthenate respectively.
The overbased detergents are referred to as being of mixed type if the micelles
comprise several types of detergents, differing from each other by the nature of their
20 hydrophobic chain.
In an embodiment of the invention, the overbased detergent and the neutral
detergent can be selected from the carboxylates, sulphonates, salicylates,
naphthenates, phenates, and the mixed detergents combining at least two of these
types of detergents.
25 In a preferred embodiment of the invention, the overbased detergent and the neutral
detergent are compounds based on metals selected from calcium, magnesium,
sodium or barium, preferentially calcium or magnesium.
In another preferred embodiment of the invention, the overbased detergent is
overbased with insoluble metallic salts selected from the group of the carbonates of
30 alkali and alkaline-earth metals, preferentially calcium carbonate.
In another preferred embodiment of the invention, the overbased detergent is
selected from the phenates, sulphonates, salicylates and the mixed phenate -
sulphonate - salicylate detergents, overbased with calcium carbonate, more
35 preferentially sulphonates and phenates overbased with calcium carbonate.
In the cylinder lubricants according to the invention, a part of the BN is provided by
the insoluble metallic salts of the overbased detergent, in particular the metallic
carbonates.
The BN provided by the metallic carbonate salts (or carbonate BN or BNcacoa) is
5 measured on the overbased detergent alone and/or on the final lubricant according
to the method described hereafter. Typically in an overbased detergent, the BN
provided by the metallic carbonate salts represents from 50 to 95% of the total BN of
the overbased detergent alone.
It is to be noted that certain neutral detergents also comprise a certain content
10 (much lower than the overbased detergents) of insoluble metallic salts (calcium
carbonate), and can themselves contribute to the carbonate BN.
In an embodiment of the invention, the percentage by mass of the overbased
detergent with respect to the total weight of the cylinder lubricant is selected so that
the BN provided by the metallic carbonate salts represents a contribution ranging
15 from 20 to 90 milligrams of potash per gram of lubricant, preferentially from 30 to 70
milligrams of potash per gram of lubricant, to the total BN of said cylinder lubricant.
In another embodiment of the invention, the percentage by mass of the overbased
detergent with respect to the total weight of the cylinder lubricant is selected so that
the BN provided by the metallic carbonate salts represents a contribution strictly
20 greater than 20 milligrams of potash per gram of lubricant to the total BN of said
cylinder lubricant.
In a preferred embodiment of the invention, the percentage by mass of the
overbased detergent with respect to the total weight of the cylinder lubricant is
selected so that the BN provided by the metallic carbonate salts represents a
25 contribution greater than 20 milligrams of potash per gram of lubricant and less than
or equal to 90 milligrams of potash per gram of lubricant and below, preferably
ranging from 30 to 70 milligrams of potash per gram of lubricant to the total BN of
said cylinder lubricant.
These insoluble metallic salts have a favourable anti-wear effect as long as they are
30 maintained dispersed in the lubricant in the form of stable micelles.
Moreover, the actual detergents, which can be detergent soaps of the essentially
phenate, sulphonate, or salicylate type, also contribute to the BN of the cylinder
lubricants according to the invention.
35 The BN of the cylinder lubricants according to the invention, measured according to
ASTM D2896 therefore comprises several distinct components, including at least:
1) The BN provided by the insoluble metallic salts of the overbased and neutral
detergents, called by extension "carbonate BN" or "BNcaco$l, and measured
by the method described hereafter,
2 ) The additional BN, hereafter denoted "organic BN", which can be measured
by the difference between the total ASTM D-2896 BN of the lubricant and its
carbonate BN, and provided:
o by the metallic soaps of the overbased and optionally neutral
detergents,
o by the fatty amines, (this amine BN being determined as a
function of the BN of the amines measured by ASTM D-2896 and the
percentage by mass of fatty amines).
In an embodiment of the invention, the percentage by mass of the overbased
detergent and of the neutral detergent with respect to the total weight of the cylinder
lubricant, is selected s o that the organic BN provided by the detergent soaps can
represent a contribution of at least 10 milligrams of potash per gram of lubricant,
preferentially ranging from 10 to 60 milligrams of potash per gram of lubricant, more
preferentially from 10 to 40 milligrams of potash per gram of lubricant to the total BN
of said cylinder lubricant.
In another embodiment of the invention, the percentage by mass of the overbased
detergent with respect to the total weight of cylinder lubricant can range from 8 to
30%, preferably from 10 to 30%.
In another embodiment of the invention, the percentage by mass of the neutral
detergent with respect to the total weight of cylinder lubricant can range from 5 to
15%, preferably from, 5 to 10%.
The BN of the cylinder lubricants according to the present invention is provided by at
least one overbased detergent based on alkali or alkaline-earth metals, at least one
neutral detergent and at least one fatty amine of formula (I).
The value of this BN, measured according to the standard ASTM D-2896 is greater
than or equal to 50 milligrams of potash per gram of lubricant.
The BN of a cylinder lubricant for marine engines will be selected depending on the
conditions of use of said lubricants and in particular according to the sulphur content
of the fuel oil used in association with said cylinder lubricants.
In an embodiment of the invention, the BN of the cylinder lubricant can range from
50 to I00 milligrams of potash per gram of lubricant, preferably from 60 to 90
milligrams of potash per gram of lubricant.
In a preferred embodiment of the invention, the BN of the cylinder lubricant ranges
from 65 to 80 milligrams of potash per gram of lubricant, preferably from 65 to 75
milligrams of potash per gram of lubricant.
Lubricant base oils
In general, the lubricant base oils used for the formulation of cylinder lubricants
according to the present invention can be oils of mineral, synthetic or vegetable
origin as well as mixtures thereof.
The mineral or synthetic oils generally used in the application belong to one of
groups I to V according to the classes defined in the API classification (or their
equivalents according to the ATIEL classification) as summarized below. Moreover,
the lubricant base oil(s) used in the cylinder lubricants according to the invention can
be selected from the oils of synthetic origin of group VI according to the ATIEL
classification. The API classification is defined in American Petroleum Institute 1509
"Engine oil Licensing and Certification System" 17th edition, September 2012.
The ATIEL classification is defined in "The ATIEL Code of Practice", number 18,
November 201 2.
25 *for the ATIEL classification only
Group I Mineral oils
Group II Hydrocracked oils
Group Ill
Hydrocracked or hydroisomerized
oils
Saturates
content
< 90%
2 90%
2 90%
Sulphur
content
> 0.03%
10.03%
10.03%
Group IV
Group V
Group VI*
Viscosity index
80 1 VI < 120
80 I V I < 120
2 120
PA0 (Poly alpha olefins)
Esters and other bases not included in bases of
groups l to lV
Poly Internal Olefins (PIO)
The mineral oils of Group I can be obtained by distillation of selected naphthenic or
paraffinic crudes then purification of these distillates by processes such as solvent
extraction, solvent or catalytic dewaxing, hydrotreatment or hydrogenation.
The oils of Groups I I and I l l are obtained by more severe purification processes, for
5 example a combination of hydrotreating, hydrocracking, hydrogenation and catalytic
dewaxing.
The examples of synthetic bases of Group IV and V include the polyisobutenes,
alkylbenzenes and poly alpha olefins such as the polybutenes.
These lubricant base oils can be used alone or in a mixture. A mineral oil can be
10 combined with a synthetic oil.
Cylinder oils for two-stroke marine engines have a viscosimetric grade of SAE-40 to
SAE-60, generally SAE-50 equivalent to a kinematic viscosity at 100°C comprised
between 16.3 and 21.9 mm2/s measured according to the standard ASTM D445.
The oils of grade SAE-40 have a kinematic viscosity at 100°C comprised between
15 12.5 and 16.3 cSt measured according to the standard ASTM D445.
The oils of grade SAE-50 have a kinematic viscosity at 100°C comprised between
16.3 and 21.9 cSt measured according to the standard ASTM D445.
The oils of grade SAE-60 have a kinematic viscosity at 100°C comprised between
21.9 and 26.1 cSt measured according to the standard ASTM D445.
20
In a preferred embodiment of the invention, the cylinder lubricants have a kinematic
viscosity measured according to the standard ASTM D445 at 100°C ranging from
12.5 to 26.1 cSt, preferentially from 16.3 to 21.9 cSt.
25 This viscosity can be obtained by mixing additives and base oils for example ,
containing mineral bases of Group I such as Neutral Solvent bases (for example 500
NS or 600 NS) and Brightstock. Any other combination of bases, mineral, synthetic
or of vegetable origin having, in a mixture with the additives, a viscosity compatible
with the grade SAE-50 can be used.
30 Typically, a standard formulation of cylinder lubricant for two-stroke marine engines
is of grade SAE-40 to SAE-60, preferentially SAE-50 (according to the classification
SAE J300) and comprises at least 40% by weight of lubricant base oil of mineral, or
synthetic origin or mixtures thereof, adapted to use for a marine engine. For
example, a lubricant base oil of group I according to the API classification, i.e.
35 obtained by the following operations: distillation of selected crudes then purification
of these distillates by processes such as solvent extraction, solvent or catalytic
dewaxing, hydrotreatment or hydrogenation, can be used for the formulation of a
cylinder lubricant. The lubricant base oils of group I have a Viscosity Index (VI)
ranging from 80 to 120; their sulphur content is greater than 0.03% and their content
of saturated hydrocarbon-containing compounds is less than 90%.
. 5 Typically, a standard formulation of cylinder lubricant for two-stroke marine engines
contains from 18 to 25% by weight, with respect to the total weight of lubricant, of a
group I base oil of BSS type (distillation residue, with a kinematic viscosity of 100°C of
approximately 30 mm2/s, typically from 28 to 32 mm2/s, and with a density at 15°C
ranging from 895 to 915 kg/m3), and from 50 to 60% by weight, with respect to the total
10 weight of lubricant, of a group I base oil of the 600 NS type (distillate, with a density at
15°C ranging from 880 to 900 kg/m3, with a kinematic viscosity of 100°C of
approximately 12 mmYs).
Other additives
In an embodiment of the invention, the cylinder lubricant can also comprise an
additional compound selected from:
20 - the primary, secondary or tertiary fatty monoalcohols, the alkyl chain of
which is linear or branched, saturated or unsaturated and comprising at
least 12 carbon atoms, preferentially from 12 to 24 carbon atoms, more
preferentially from 16 to 18 carbon atoms, advantageously the primary
monoalcohols with a saturated, linear alkyl chain,
25 - the esters of saturated fatty monoacids comprising at least 14 carbon
atoms and alcohols comprising at most 6 carbon atoms, preferentially the
mono- and diesters, advantageously the monoesters of monoalcohols and
the diesters of polyols, the ester functions of which are at a distance of four
carbon atoms at most, counting from the oxygen side of the ester function.
30
In a preferred embodiment of the invention, the cylinder lubricant also comprises an
additional compound selected from the primary, secondary or tertiary fatty
monoalcohols, the alkyl chain of which is linear or branched, saturated or
unsaturated and comprising from 16 to 18 carbon atoms, advantageously the
35 primary monoalcohols with a saturated, linear alkyl chain.
In an embodiment of the invention, the content of additional compound as defined
above ranges from 0.01 to lo%, preferably from 0.1 to 2% by weight with respect to
the total weight of the cylinder lubricant.
5 The cylinder lubricant can also comprise at least one other additional additive
selected from the dispersants, the anti-wear additives or any other functional
additive.
The dispersants are well-known additives used in the lubricant composition
10 formulation, in particular for application in the marine field. Their primary role is to
maintain in suspension the particles initially present or appearing in the lubricant
during its use in the engine. They prevent their agglomeration by acting on the steric
hindrance. They can also have a synergistic effect on neutralization.
15 The dispersants used as lubricant additives typically contain a polar group,
associated with a relatively long hydrocarbon-containing chain, generally containing
from 50 to 400 carbon atoms. The polar group typically contains at least one
nitrogen, oxygen or phosphorus element.
The compounds derived from succinic acid are dispersants particularly used as
20 lubrication additives. In particular succinimides obtained by condensation of succinic
anhydrides and amines, the succinic esters obtained by condensation of succinic
anhydrides and of alcohols or polyols are used.
These compounds can then be treated with various compounds in particular
sulphur, oxygen, formaldehyde, carboxylic acids and compounds containing boron
25 or zinc in order to produce for example borated succinimides or zinc-blocked
succinimides.
Mannich bases, obtained by polycondensation of phenols substituted with alkyl
groups, formaldehyde and primary or secondary amines, are also compounds used
as dispersants in the lubricants.
30 In an embodiment of the invention, the dispersant content cari be greater than or
equal to 0.1%, preferably from 0.5 to 2%, advantageously from 1 to 1.5% by weight
with respect to the total weight of the cylinder lubricant.
The anti-wear additives protect the friction surfaces by forming a protective film
35 adsorbed on these surfaces. The most commonly used is zinc dithiophosphate or
DTPZn. Various phosphorus-, sulphur-, nitrogen-, chlorine- and boron-containing
compounds are also found in this category.
A great variety of anti-wear additives exists, but the most frequently used category is
that of the phospho sulphur-containing additives such as the metallic
alkylthiophosphates, in particular zinc alkylthiophosphates, and more specifically
zinc dialkyldithiophosphates or DTPZn. The preferred compounds are of formula
Zn((SP(S)(OR3)(0R4))2, wherein R3 and R4 are alkyl groups, preferentially
comprising from 1 to 18 carbon atoms. The DTPZn is typically present in contents of
the order of 0.1 to 2% by weight with respect to the total weight of the cylinder
lubricant.
The amine phosphates, the polysulphides, in particular the sulphur-containing
olefins, are also commonly-used anti-wear additives.
Anti-wear and extreme pressure additives of the nitrogen- and sulphur-containing
type, such as for example the metallic dithiocarbamates, in particular molybdenum
dithiocarbamate, are also usually found in cylinder lubricants. The glycerol esters
are also anti-wear additives. For example the mono-, di and trioleates,
monopalmitates and monomyristates may be mentioned.
In an embodiment, the anti-wear additive content ranges from 0.01 to 6%,
preferentially from 0.1 to 4% by weight with respect to the total weight of the cylinder
lubricant.
The other functional additives can be selected from the thickeners and the antifoaming
additives in order to counteract the effect of the detergents, which can be
for example polar polymers such as polymethylsiloxanes, polyacrylates, the antioxidant
and/or anti-rust additives, for example organo-metallic detergents or
thiadiazoles. The latter are known to a person skilled in the art. These additives are
generally present in a content by weight of 0.1 to 5% with respect to the total weight
of the cylinder lubricant.
In a preferred embodiment of the invention, the cylinder lubricant comprises:
- from 55 to 85% of at least one base oil,
-from 2 to 10% of a mixture of fatty amines comprising at least one fatty amine of
formula (I) and in which the content by weight of fatty amine of formula (I) is greater
than or equal to 90%, preferentially strictly less than loo%, advantageously from 90
to 99.9% with respect to the total weight of the mixture of fatty amines,
-from 8 to 30% of at least one detergent based on alkali or alkaline-earth metals,
overbased with metallic carbonate salts,
-from 5 to 15% of at least one neutral detergent.
26
In another preferred embodiment of the invention, the cylinder lubricant essentially
consists of:
- 55 to 85% of at least one base oil,
- 2 to 10% of a mixture of fatty amines comprising at least one fatty amine of formula
(I) and in which the content by weight of fatty amine of formula (I) is greater than or
equal to 90%, preferentially strictly less than 100%, advantageously from 90 to
99.9% with respect to the total weight of the mixture of fatty amines,
- 8 to 30% of at least one detergent based on alkali or alkaline-earth metals,
overbased with metallic carbonate salts,
- 5 to 15% of at least one neutral detergent.
All of the characteristics and preferences presented for the base oil, the fatty amine,
the overbased detergent and the neutral detergent, the contribution of the fatty
ami.ne of formula (I) and the contribution of the overbased detergent to the total BN
of the lubricant also apply to the above cylinder lubricants.
In a preferred embodiment of the invention, the cylinder lubricant comprises:
-from 45 to 84.99% of at least one base oil,
-from 2 to 10% of a mixture of fatty amines comprising at least one fatty amine of
formula (I) and in which the content by weight of fatty amine of formula (I) is greater
than or equal to 90°h, preferentially strictly less than loo%, advantageously from 90
to 99.9% with respect to the total weight of the mixture of fatty amines,
-from 8 to 30% of at least one detergent based on alkali or alkaline-earth metals,
overbased with metallic carbonate salts,
- from 5 to 15% of at least one neutral detergent,
-from 0.01 to 10% of at least one additional compound selected from the primary,
secondary or tertiary fatty monoalcohols, the alkyl chain of which is linear or
branched, saturated or unsaturated and comprising at least 12 carbon atoms,
preferentially from 12 to 24 carbon atoms, more preferentially from 16 to 18 carbon
atoms, advantageously the primary monoalcohols with a saturated, linear alkyl
chain.
In another preferred embodiment of the invention, the cylinder lubricant essentially
consists of:
- 45 to 84.99% of at least one base oil,
- 2 to 10% of a mixture of fatty amines comprising at least one fatty amine of formula
(I) and in which the content by weight of fatty amine of formula (I) is greater than or
equal to 90%, preferentially strictly less than loo%, advantageously from 90 to
99.9% with respect to the total weight of the mixture of fatty amines,
- 8 to 30% of at least one detergent based on alkali or alkaline-earth metals,
overbased with metallic carbonate salts,
- 5 to 15% of at least one neutral detergent,
- 0.01 to 10% of at least one additional compound selected from the primary,
secondary or tertiary fatty monoalcohols, the alkyl chain of which is linear or
branched, saturated or unsaturated and comprising at least 12 carbon atoms,
preferentially from 12 to 24 carbon atoms, more preferentially from 16 to 18 carbon
atoms, advantageously the primary monoalcohols with a saturated, linear alkyl
chain.
All of the characteristics and preferences presented for the base oil, the fatty amine,
ovecbased detergent, neutral detergent and additional compound, the contribution of
the fatty amine of formula (I) and the contribution of the overbased detergent to the
total BN of the lubricant also apply to the above cylinder lubricants.
A subject of the invention is also the use of a cylinder lubricant as defined above for
lubricating a two-stroke marine engine.
All of the character is ti.^^ and preferences presented for the cylinder lubricant also
apply to the above use.
A subject of the invention is also the use of a cylinder lubricant as defined above as
a single cylinder lubricant that can be used both with fuel oils with a sulphur content
of less than 1 % by weight with respect to the total weight of the fuel oil, with fuel oils
with a sulphur content ranging from 1 to 3.5% by weight with respect to the total
weight of the fuel oil and with fuel oils with a sulphur content greater than 3.5% by
weight with respect to the total weight of the fuel oil.
In an embodiment, a subject of the invention is the use of a cylinder lubricant as
defined above as a single cylinder lubricant that can be used both with fuel oils with
a sulphur content of less than 1% by weight with respect to the total weight of the
fuel oil and with fuel oils with a sulphur content ranging from I to 3.5% by weight
with respect to the total weight of the fuel oil.
All of the characteristics and preferences presented for the cylinder lubricant also
apply to the above use.
A subject of the invention is also the use of a cylinder lubricant as defined above in
order to prevent corrosion and/or reduce the formation of insoluble metallic salt
deposits in two-stroke marine engines during the combustion of any type of fuel oil
the sulphur content of which is less than or equal to 3.5% by weight with respect to
5 the total weight of the fuel oil.
All of the characteristics and preferences presented for the cylinder lubricant also
apply to the above use.
The compounds as defined above and contained in the cylinder lubricant according
10 to the invention, and more particularly the fatty amine of formula (I), the detergent
based on alkali or alkaline-earth metals, overbased with metallic carbonate salts and
the neutral detergent, can be incorporated in the cylinder lubricant as separate
additives, in particular by the separate addition thereof t o t h e b a s e oils.
However, they can also be incorporated in an additive concentrate for cylinder
15 lubricants.
Thus, a subject of the invention is also an additive concentrate for the preparation of
cylinder lubricant having a BN determined according to the standard ASTM D-2896
greater than or equal to 50 milligrams of potash per gram of lubricant, said
'20 concentrate having a BN ranging from 100 to 400 mg of potash per gram of
concentrate, and comprising at least one detergent based on alkali or alkaline-earth
metals, overbased with metallic carbonate salts, at least one neutral detergent and
at least one fatty amine having a BN ranging from 150 to 600 mg of potashlg of
amine according to the standard ASTM D-2896 and of formula (I):
25 Rl-[NR2(CH2)313-NH2
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
3 0 R2 represents a hydrogen atom or a -(CH2)20H group,
the percentage by mass of said fatty amine in the concentrate being selected so as
to provide said concentrate with a contribution of BN determined according to the
standard ASTM D-2896 ranging from 20 to 300 milligrams of potash per gram of
concentrate.
35 '
All of the characteristics and preferences presented for the fatty amine of formula (I)
also apply to t h e above additive concentrate.
In an embodiment of the invention, the additive concentrate can comprise:
- at least one detergent based on alkali or alkaline-earth metals, overbased with
metallic carbonate salts,
- at least one neutral detergent,
- at least one additional compound selected from the primary, secondary or tertiary
fatty monoalcohols, the alkyl chain of which is linear or branched, saturated or
unsaturated, and comprising at least 12 carbon atoms, preferentially from 12 to 24
carbon atoms, more preferentially from 16 to 18 carbon atoms, advantageously the
primary monoalcohols with a saturated, linear alkyl chain.
- at least one fatty amine having a BN ranging from 150 to 600 mg of potashlg of
amine according to the standard ASTM D-2896 and of formula (I):
Rl-[NR2(cH2)313'NH2
(1)
in which:
15 R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH2)20H group.
In another embodiment of the invention, the additive concentrate can comprise:
20 - from 30 to 71% of at least one detergent based on alkali or alkaline-earth metals,
overbased with metallic carbonate salts,
- from 20 to 50% of at least one neutral detergent,
- from 9 to 30% of at least one fatty amine having a BN ranging from 150 to 600 mg
of potashlg of amine according to the standard ASTM D-2896 and of formula (I):
25 Rl-[NR2(CH2)313'NH2
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
3 0 R2 represents a hydrogen atom or a -(CH2)20H group.
In another embodiment of the invention, the additive concentrate can comprise:
- from 30 to 70.6% of at least one detergent based on alkali or alkaline-earth metals,
overbased with metallic carbonate salts,
35 - from 20 to 50% of at least one neutral detergent,
-from 0.4 to 25% of at least one additional compound selected from the primary,
secondary or tertiary fatty monoalcohols, the alkyl chain of which is linear or
branched, saturated or unsaturated and comprising at least 12 carbon atoms,
preferentially from 12 to 24 carbon atoms, more preferentially from 16 to 18 carbon
atoms, advantageously the primary monoalcohols with a saturated, linear alkyl
chain.
- from 9 to 30% of at least one fatty amine having a BN ranging from 150 to 600 mg
of potashlg of amine according to the standard ASTM D-2896 and of formula (I):
RI-[NR~(CH~)~I~-NHZ
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CHz)20H group.
All of the characteristics and preferences presented for the fatty amine, overbased
detergent, neutral detergent and additional compound also apply to the above
15 additive concentrates.
In an embodiment of the invention, at least one base oil can be added to the additive
concentrate according to the invention in order to obtain a cylinder lubricant
according to the invention.
20
Another subject of the invention relates to a method for lubricating a two-stroke
marine engine, said method comprising at least one step of bringing the engine into
contact with a cylinder lubricant as described previously or obtained from an additive
concentrate as described previously.
,25 All of the characteristics and preferences presented for the cylinder lubricant or for
the additive concentrate also apply to the above lubrication method.
Another subject of the invention relates to a method for preventing corrosion andlor
reducing the formation of insoluble metallic salt deposits in two-stroke marine
30 engines during the combustion of any type of fuel oil the sulphur content of which is
less than 3.5% with respect to the total weight of the fuel oil, comprising at least one
step of bringing the engine into contact with a cylinder lubricant as defined above or
obtained from the additive concentrate as described previously.
All of the characteristics and preferences presented for the cylinder lubricant or for
35 the additive concentrate also apply to the above method.
The different subjects of the present invention and their implementations will be
better understood on reading the following examples. These examples are given as
an indication, without being limitative in nature.
5 Method for measuring the contribution of the insoluble metallic salts present in the
overbased detergents to the BN of the cylinder lubricants containing said overbased
detergents
The method making it possible to measure the contribution of the insoluble metallic
salts present in the overbased detergents to the BN of the cylinder lubricants
10 containing said overbased detergents is defined as follows:
The total measurement of the basicity (referred to as BN or Base Number) of the
cylinder lubricants or of the overbased detergents is carried out by the method
ASTM D2896. This BN is composed of two distinct forms:
= carbonate BN, provided by overbasing the detergent with metallic carbonates,
15 generally calcium carbonate, hereafter denoted "BNCaC0311,
= so-called organic BN provided by the metallic soap of the detergent of the
essentially phenate or salicylate, or sulphonate type.
Carbonate BN, hereafter denoted BNcaco3 is measured, on the cylinder lubricant or
the overbased detergents alone, according to the following procedure. This operates
20 on the principle of attacking the overbasing, (calcium) carbonate, of the sample with
sulphuric acid. This carbonate is converted to calcium sulphate with release of
carbonic gas following the reaction;
The volume of the reactor being constant, the pressure increases in proportion to
the release of C02. u
Procedure: in a reaction vessel with a volume of 100 ml, equipped with a stopper on
which a differential manometer is fitted, the necessary quantity of product the BNcaco3 of
30 which is to be measured, is weighed so as not to exceed the measurement limit of the
differential manometer, which is 600 mb (mb=millibar) of pressure increase. The
quantity is determined from the graph in Figure 2, indicating for each mass of product (1
to 10 grams) the pressure measured on the differential manometer (which corresponds
to the pressure increase due to the release of Con) as a function of the proportion of
35 BNcaco3 in the sample. If the result of BNcaco3 is unknown, a moderate quantity of
product of approximately 4 g is weighed. In all cases, the sample mass is noted (m).
The reaction vessel can be made of Pyrex, glass, polycarbonate, etc. or any other
material promoting heat exchanges with the ambient medium, such that the internal
temperature of the vessel rapidly reaches equilibrium with that of the ambient
medium.
A small quantity of fluid base oil, of the 600 NS type, is introduced into the reaction
5 vessel containing a small magnetic bar.
Approximately 2 ml of concentrated sulphuric acid is placed in the reaction vessel,
taking care not to stir the medium at this stage.
The stopper and manometer assembly is screwed onto the reaction vessel. The
screw threads can be greased. ~ i ~ h t e nisi nca~rr ied out to ensure a complete seal.
10 Stirring is commenced, and continued for as long as necessary for the pressure to
stabilize, and for the temperature to reach equilibrium with the ambient medium. A
period of 30 minutes is sufficient. The increase in pressure P and ambient
temperature T°C (o) are noted.
The assembly is cleaned with a heptane-type solvent.
,15
Calculation method
In order to calculate the pressure the ideal gas law is used.
P V = n R T
P = Partial pressure of C02(Pa) ( IPa = lo-' mb)
20 V = Volume of the container (m3).
R = 8.32 (J).
T = 273 + o("C) = ("K).
n = number of moles of COP released
25 Calculation of the number of moles of Cop.
m *carbonate BN = mg KOH equivalent.
m = mass of product in grams
30 carbonate BN = BN expressed in KOH equivalent per lg.
44 rn * carbonateBN * -
2*56.1 = g of C02released, i.e. the number of moles of COP
1000
released:
m * carbonate BN * 44 * 1 o - ~ = m * carbonate BN * 0.0089 10"
44*2*56.1
35 Formula for calculation of the Pressure of C0-7 as a function of the carbonate BN.
P COa =
m *carbonate EN *0.0089 10" * R * ~*10-'
v
k Formula for calculation of the carbonate BN from the pressure of C02.
carbonate BN =
P*V
m*0.0089*10-~* RXT*lO-'
By fixing the values linked to the test conditions, the simplified formula is obtained:
P C02 = value read on the differential manometer, in mbars = P read
10 V = volume of the container in m3 = 0.0001.
R = 8.32 (J).
T = 273 + o ("C) = ("K). o = Ambient temperature read.
m = mass of product introduced into the reaction vessel.
carbonate EN= P read * 0.0001
m *0.0089*10" * 8.32 * (273 *oread) * lo-'
carbonate EN = P read
m * 0.0074* R * (273.* oread)
20
The result obtained is the BNcaco3e xpressed in mgKOHIg.
The BN provided by the metallic soaps of detergents, also referred to as "organic
BN", is obtained by the difference between the total BN according to ASTM D2896
and the BNcaco3th us measured.
Enthalpy test measuring the neutralization efficiency of the lubricants vis-a-vis
sulphuric acid
The enthalpy test making it possible to measure the neutralization efficiency of the
lubricants vis-a-vis sulphuric acid is defined as follows.
30 The availability or accessibility of the basic sites included in a lubricant, in particular
cylinder lubricant for two-stroke marine engines, vis-a-vis acid molecules, can be
quantified by a dynamic test monitoring the neutralization rate or kinetics.
Principle:
Acid-base neutralization reactions are generally exothermic and it is therefore
35 possible to measure the release of heat obtained by reacting sulphuric acid with the
lubricants to be tested. This release is monitored by the evolution of the temperature
over time in an adiabatic reactor of the Dewar type.
Based on these measurements, it is possible to calculate an index quantifying the
efficiency of a lubricant according to the present invention compared with a lubricant
5 used as a reference, and for an added quantity of acid representing a fixed number
of BN points to be neutralized. In order to test lubricants with a BN of 70, in the
examples which follow, a quantity of acid corresponding to the neutralization of 70
BN points is thus added.
The efficiency index is thus calculated relative to the reference oil to which the value
10 of 100 is assigned. This is the ratio between the neutralization reaction times of the
reference (Sref) and the measured sample (S,):
Neutralization efficiency index = Sref/S,,, x 100
The values of these neutralization reaction times, which are of the order of a few
15 seconds, are determined from the acquisition curves of the increase in temperature
as a function of time during the neutralization reaction. (See curve in figure 1).
The duration S is equal to the difference tf - ti between the time at the temperature at
the end of the reaction and the time at the temperature at the start of the reaction.
The time ti at the temperature at the start of the reaction corresponds to the first rise
,20 in temperature after stirring is started.
The time tf at the temperature at the end of the reaction is the time from which the
temperature signal remains stable for a period of time greater than or equal to half
the reaction time.
The lubricant is all the more efficient as it leads to short neutralization times and
25 therefore to a high index.
Equipment used:
The geometries of the reactor and of the stirrer as well as the operating conditions
were selected so that they are situated in the chemical regime, where the effect of
30 the diffusional constraints in the oil phase is negligible.
Therefore, in the configuration of the equipment used, the height of fluid must be
equal to the internal diameter of the reactor, and the helical stirrer must be
positioned at approximately 113 of the height of the fluid.
The equipment is constituted by a 300 ml adiabatic reactor of a cylindrical type, the
35 internal diameter of which is 52 mm and the internal height 185 mm, with a stirring
rod equipped with a helix with inclined blades, 22 mm in diameter; the diameter of
the blades is comprised between 0.3 and 0.5 times the diameter of the Dewar flask,
i.e. 15.6 to 26 mm.
The position of the helix is fixed at a distance of approximately 15 mm from the base
of the reactor. The stirring system is driven by a 10 to 5,000 rpm variable speed
motor and a system for acquiring the temperature as a function of time.
This system is suitable for measuring reaction times of the order of 5 to 20 seconds
5 and for measuring the rise in temperature of a few tens of degrees starting from a
temperature of approximately 20°C to 35"C, preferably approximately 30°C. The
position of the temperature acquisition system in the Dewar flask is fixed.
The stirring system will be controlled in such a way that the reaction takes place
within a chemical range: in the configuration of the present experiment, the rotation
10 speed is adjusted to 2000 rpm, and the position of the system is fixed.
Moreover, the chemical range of the reaction is also dependent on the depth of the
oil introduced into the Dewar flask, which must be equal to the diameter of the flask,
and which corresponds in the context of this experiment to a mass of approximately
86 g of the lubricant tested.
, 15 In order to test lubricants with a BN of 70, here the quantity of acid corresponding to
the neutralization of 70 BN points is introduced into the reactor.
7.01 g of sulphuric acid concentrated to 75% and 86 g of lubricant to be tested are
introduced into the reactor, for a lubricant with a BN of 70.
After placing the stirring system inside the reactor so that the acid and the lubricant
20 mix well and in a reproducible manner between two tests, stirring is started in order
to follow the reaction within a chemical range. The acquisition system is permanent.
Implementation of the enthalpy test - calibration:
25 In order to calculate the efficiency indices of the lubricants according to the present
invention using the method described above, we chose to take as a reference the
neutralization reaction time measured for a cylinder lubricant for two-stroke marine
engines LEf with a BN of 70 mg KOH/g of lubricant (measured by ASTM D-2896),
containing no fatty amines according to the present invention.
30 This cylinder lubricant is obtained from a mineral lubricant base oil obtained by
mixing a distillate with a density at 15°C comprised between 880 and 900 Kg/m3
with a distillation residue with a density comprised between 895 and 915 Kg/m3
(Brightstock) in a distillate / residue ratio of 3.
A concentrate containing an overbased calcium sulphonate with a BN equal to 400
35 mg KOH/g, a dispersant, an overbased calcium phenate with a BN equal to 250 mg
KOH/g is added to this lubricant base. This cylinder lubricant is formulated
specifically to have a neutralization capacity sufficient to be used with fuels with a
high sulphur content, namely sulphur contents greater than 3% or even 3.5% with
respect to the total weight of the fuel oil.
This reference lubricant contains 25.50% by mass of this concentrate. Its BN of 70
mg KOH/g of lubricant is provided exclusively by the overbased detergents
(overbased phenates.and sulphonates) contained in.said concentrate.
This reference lubricant has a viscosity at 100°C comprised between 18 and 21.5 mm2/s
measured according to the standard ASTM D445.
The neutralization reaction time of this oil (hereafter reference oil Href) is 75
seconds and its neutralization efficiency index is set at 100.
EXAMPLES
Example 1: assessment of the thermal resistance properties of cylinder
lubricants according to the invention
The thermal resistance of cylinder lubricants according to the invention is assessed
by implementation of the continuous ECBT test, and the engine cleanliness in the
presence of such compositions is thus simulated.
To this end, different cylinder lubricants were prepared frdm the following
compounds:
- lubricant base oil 1: mineral oils of group I or Brightstock with a density comprised
between 895 and 915 Kg/m3,
- lubricant base oil 2: mineral oils of group I, in particular referred to as Neutral 600
NS with a viscosity at 40°C of 120 cSt measured according to the standard ASTM
D7279,
-detergent package comprising a neutral phenate with a BN equal to 150 mg KOH/g
of phenate, an overbased phenate with a BN equal to 250 mg KOH/g of overbased
phenate, an overbased sulphonate with a BN equal to 400 mg KOHIg of overbased
sulphonate, a dispersant of the PIB succinimide type, a fatty alcohol which is a
mixture of monoalcohols having a hydrocarbon-containing chain comprising from 16
to 18 carbon at-oms and an anti-foaming agent,
- fatty amine 1: mixture comprising 99.9% by weight of a fatty amine of formula (I) in
which R1 is an alkyl group comprising from 14 to 16 carbon atoms, R2 is a hydrogen
atom, a fatty amine of formula (I) in which R1 is an alkyl group comprising 18 carbon
atoms, R2 is a hydrogen atom, and a fatty amine of formula (I) in which .R1 is an alkyl
group comprising at least 20 carbon atoms, R2 is a hydrogen*atom, and having a BN
measured according to the standard ASTM D-2896 equal to 471 mg of potash per
gram of amine (Tetrameen OV from the company AKZO NOBEL),
-fatty amine 2: mixture comprising 99.9% of a fatty triamine comprising an alkyl
group comprising from 14 to 16 carbon atoms, a fatty triamine comprising an alkyl
group comprising 18 carbon atoms and a fatty triamine comprising an alkyl group
comprising at least 20 carbon atoms and having a BN measured according to the
' 5 standard ASTM D-2896 equal to 420 mg of potash per gram of amine (Triameen OV
from the company AKZO NOBEL).
The cylinder lubricants L1 and L2 are described in Table I; the percentages indicated
correspond to percentages by mass.
I I (invention) I (comparative) I
Table I
Compositions
I I
LI
Base oil 1
, I
L2
I I
27
Base oil 2 49
Detergent
package
Fatty amine 1
The characteristics of the cylinder lubricants L1 and L2 are described in Table II.
27
49
3.4
Fatty amine 2
20.6
3.4
I (invention) I (comparative) I
20.6
I
Table I1
Com positions L2 I
I I
the fatty amine (mg
KOHIg, ASTM D-2896)
Of which BN provided by
LI
I I
the metallic carbonate
salts (mg KOHIg, ASTM
D-2896)
Total BN 68
15 The thermal resistance of the lubricants L1 and L2 was therefore assessed by means
of the continuous ECBT test, measuring the mass of deposits (in mg) generated
under defined conditions. The lower this mass, the better the thermal resistance and
therefore the better the engine cleanliness.
68
Of which BN provided by 16 14.2
This test simulates an engine piston brought to a high temperature onto which the
lubricant from the crankcase is sprayed.
The test utilizes aluminium beakers which simulate the shape of pistons. These
beakers were placed in a glass container, maintained at a controlled temperature of
5 the order of 60°C. The lubricant was placed in these containers, themselves
equipped with a wire brush, partially immersed in the lubricant. This brush was
actuated with a rotary movement at a speed of 1000 rpm, which creates a spray of
lubricant onto the lower surface of the beaker. The beaker was maintained at a
temperature of 310°C by an electrical heating resistance, regulated by a
10 thermocouple.
In the continuous ECBT test, the test lasted 12 hours and the spray of lubricant was
continuous throughout the duration of the test. This procedure makes it possible to
simulate the formation of deposits in the piston-ring assembly. The result is the
weight of deposits measured on the beaker.
15 A detailed description of this test is given in the publication entitled "Research and
Development of Marine Lubricants in ELF ANTAR France - The relevance of
laboratorytests in simulating field performance" by Jean-Philippe ROMAN, MARINE
PROPULSION CONFERENCE 2000 -AMSTERDAM - 29-30 MARCH 2000.
20 The results are given in Table Ill below.
In Table Ill, the result obtained for the cylinder reference lubricant Lref described
above has been added.
Table Ill
The results show that the cylinder lubricants according to the i
25 thermal resistance and thus make it possible to improve engine cleanliness.
It is to be noted that the specific selection of a tetra-amine of formula (I) in which R,
is an alkyl group comprising from 16 to 20 carbon atoms makes it possible to
improve the thermal resistance with respect to a triamine also containing an alkyl
30 group comprising from 16 to 20 carbon atoms.
It is also to be noted that the cylinder lubricant according to the invention has a
thermal resistance that is slightly improved with respect to the reference cylinder oil.
Lref
230
Compositions
Continuous ECBT (mg)
Example 2: assessment of the thermal resistance properties of cylinder
35 lubricants according to the invention
LI
(invention)
220
L2
(comparative)
250
The thermal resistance of cylinder lubricants according to the invention is assessed
by implementation of the continuous ECBT test, and the engine cleanliness in the
presence of such compositions is thus simulated.
To this end, two cylinder lubricants L3 and Lq were prepared from the following
5 compounds:
-fatty amine 3: a mixture comprising 99.9% of a fatty amine of formula (I) in which
R1 is an unsaturated alkyl group comprising from 18 to 20 carbon atoms, R2 is a
hydrogen atom, and a fatty amine of formula (I) in which R1 is a saturated alkyl
group comprising from 18 to 20 carbon atoms, R2 is a hydrogen atom, and having a
10 BN measured according to the standard ASTM D-2896 equal to 477 mg of potash
per gram of amine (Tetrameen T from the company AKZO NOBEL),
-fatty amine 4: mixture comprising 99.9% of a fatty triamine comprising an
unsaturated alkyl group comprising from 18 to 20 carbon atoms, and a fatty triamine
comprising a saturated alkyl group comprising from 18 to 20 carbon atoms and a BN
15 measured according to the standard ASTM D-2896 equal to 430 mg of potash per
gram of amine (Triameen T from the company AKZO NOBEL),
- base oils I and 2 as well as the detergent package are identical to those described
in Example I
The cylinder lubricants Lg and L4 are described in Table IV; the percentages
20 indicated correspond to percentages by mass.
Table IV
Base oil 1
Base oil 2
I Fatty amine 3 ,I 3 I I
L4
(comparative)
Co'mpositions
Detergent
package
L3
(invention)
28.4
48
The characteristics of the cylinder lubricants Lg and L4 are described in - Table V.
28.4
48
20.6
I I
20.6
Fatty amine 4 3
I I (invention) I (comparative) I
Table V
Compositions
I I
I provided by the I I I
L3
Of which BN
fatty amine (mg
KOHIg, ASTM
D-2896)
L4
Total BN 64.8
Of which BN
provided by the
metallic
66
14.3
ASTM D-2896)
12.9
The thermal resistance of the lubricants L3 and L4 was therefore assessed by means
of the continuous ECBT test, as described in Example 1.
5 The results are given in Table VI.
In Table VI the result obtained for the cylinder reference lubricant Lref described
above has been added.
10 The results show that the cyl-in-d-e-r- lu brican.t-s.- -a- ccord-ing t o the invention have a good <--s - - --. -thermal resistance and thus make it pos.s.ible~to~improve.theengincele anliness.
7- --.-It is to be nozd-tEZit'th specific selection of a tetra-amine of formula (I) in which R1
Table VI
is an alkyl group comprising from 18 to 20 carbon atoms makes it possible to
improve the thermal resistance with respect to a triamine also containing an alkyl
Compositions
Continuous ECBT (mg)
15 group comprising from 18 to 20 carbon atoms.
As for Example 2, it is to be noted that the cylinder lubricant according to the
invention has a thermal resistance that is slightly improved with respect to the
L3
(invention)
,222 -
reference cylinder oil.
L4
(comparative)
259
.3aaa
Lref
230
Example 3: assessment of the properties of neutralization of cylinder
lubricants according to the invention vis-8-vis sulphuric acid
The neutralization efficiency vis-a-vis sulphuric acid of cylinder lubricants according
5 to the invention is assessed by implementation of the enthalpy test described above.
To this end, the lubricants L, and L2 as described in Example 1 were assessed, as
well as the cylinder reference lubricant LEf described above.
These results show that the use of a cylinder lubricant according to the invention
The results are described in Table VII.
10 Table VII
makes it possible to obtain a "cry good neutralization efficiency vis-a-vis sulphuric
acLid , this-efficiency being much greater t h a ? i " m m e - --- - -- oil. - - . ,-- It is to .be noted that the neutralization efficiency obtained by the use of a cylinder
Compositions
Neutralization efficiency
index
lubricant according to the invention is not far from that obtained with a cylinder
lubricant comprising a triamine.
20 . Thus, examples 1, 2 and 3 demonstrate the benefit of the specific selection of a fatty
amine of formula (I) with respect to other fatty polyamines, making it possible to
obtain both a very good neutralization efficiency and improved thermal resistance
properties, and therefore improved cleanliness of the piston-cylinder assembly.
Lref
100
LI
(invention)
405
25 Example 4: assessment of the viscosity of cylinder lubricants according to the
invention vis-a-vis sulphuric acid
The viscosity index vis-a-vis cylinder lubricants according to the invention calculated
according to the international standard ASTM D2230 is assessed.
To this end, two cylinder lubricants L5 and L6 were prepared from the following
30 compounds:
-fatty amine 5: ethoxylated oleic monoamine having a BN measured according to
the standard ASTM D-2896 equal to 160 mg of potash per gram of amine
(Ethomeen 0112 from the company AKZO NOBEL)
L2
(comparative)
588
- base oils 1 and 2; fatty amine 1 as well as the detergent package are identical to
those described in Example 1.
The cylinder lubricants Lg and L6 are described in Table VIII; the percentages
indicated correspond to percentages by mass.
Table Vlll
Compositions
Base oil 1
I I
I package I I I
LS
(invention)
30
Base oil 2
I I
L6
(comparative)
40.4
Detergent
40.4
Fatty amine 1
The characteristics of the cylinder lubricants L5 and L6 are described in Table IX.
30
20.6'
9
I I
20.6
Fatty amine 5 1
I I (invention) I (comparative) I
9
Table IX
I Total BN 1 95 1 68 1
Compositions
I provided by the I I I
Ls
Of which BN
L6
(mg KOHIg,
ASTM D-2896)
42.4
fatty amine (mg
KOHIg, ASTM
D-2896)
Of which BN
provided by the
metallic
carbonate salts
10 The results are described in Table X; the higher the viscosity index, the better the
14.4
viscosity stability as a function of the temperature.
37.3 37.3
Table X
Compositions Ls
(invention)
L6
(comparative)
These results show that the incorporation of a high content of fatty amine of formula
(I) in a cylinder lubricant makes it possible to maintain a satisfactory viscosity
stability as a function of temperature, whereas the incorporation of the same high
5 content of alkoxylated fatty amine in a cylinder lubricant degrades this stability.
Example 5: a s s e s s m e n t of t h e thermal resistance properties of cvlinder
lubricants according to the invention
The thermal resistance of cylinder lubricants according t o t h e invention is assessed
10 by implementation of the continuous ECBT test, and the engine cleanliness in the
presence of such compositions is fhus simulated.
To this end, the lubricant L7 was prepared from the following compounds:
- fatty amine 6: mixture of fatty amines comprising 80% of fatty amine of formula (I)
in which Rl is a hydrocarbon-containing chain comprising from I 6 to 20 carbon
15 atoms, R2 is a hydrogen atom, and 20% of a mixture of fatty monoamines and
diamines, and having a BN measured according to the standard ASTM D-2896
equal to 460 mg of potash per gram of amine (Polyram S from the company CECA)
- base oils I and 2 and the detergent package are identical to those described in
Example 1.
Neutralization efficiency 94
index
The cylinder lubricants L1 and L7 are described in Table XI; the percentages
104
indicated corresponding to percentages by mass.
The characteristics of the cylinder lubricants L1 and L7 are- descri bed in Table XII.
Table XI
L7
(comparative)
27
49
20.6
3.4
Com positions
Base oil 1
Base oil 2
Detergent
package
Fatty amine I
Fatty amine 6
25
LI
(invention)
27
49
20.6
. 3.4
I (invention)
Table XI1
Compositions
(comparative)
Total BN
Of which BN provided by
the fatty amine (mg
KOHIg, ASTM D-2896)
Of which BN provided by
the metallic carbonate
salts (mg KOHIg, ASTM
D-2896)
0
The thermal resistance of the lubricants L1 and L7 was therefore assessed by means
of the continuous ECBT test, as described in Example 1.
L1
6 8
16
37.3
5 The results are given in Table XIII.
L7
In Table Xlll the result obtained for the cylinder reference lubricant LEf described
abovehasbeenadded.
10 The results show that the cylinder lubricants according to the invention have a good
---N___N___-N___---- ar, thermal resistance and thus make it possible to improve engine cleanlines5
- ===---.LSE2&.-,.
?~hesere sults dem~nst~m~~-of a mixture of fatty
amines having a content by weight of fatty amine of formula (I) of at least 90% and
preferentially strictly iess than 100% with respect to the total weight of the mixture of
15 fatty amines in the cylinder lubricant.
In fact the presence of a mixture of fatty amines comprising a content by weight of
fatty amine of formula (I) of at most 80% with respect to the total weight of the
mixture in a cylinder lubricant leads to a deterioration of the thermal resistance, and
thus a degradation of the engine cleanliness.
20
Thus, examples 1, 2, 3, 4 and 5 demonstrate the benefit of the specific selection of a
mixture of fatty amines having a content by weight of fatty amine of formula (I) of at
least 90% and preferentially strictly less than 100% with respect to the total weight
of the mixture of fatty amines with respect to mixtures of fatty amines having a
Table Xlll
Compositions
Continuous ECBT (mg)
L1
(invention)
220
e
L7
(comparative)
28 1
Lref
230
content by weight of fatty amine of formula (I) less . than. 90% with respect to the total
weight of the mixture, with respect to other fatty polyamines or with respect to
alkoxylated amines,-~al$~g&~-~siblteo obtain both a ~ ~ ~ a t i 2fficiency and improved thermal resistance properties, wsatisfactory viscosity stability over time. -

CLAIMS
1 Cylinder lubricant having a BN determined according to the standard ASTM
D-2896 greater than or equal to 50 milligrams of potash per gram of lubricant,
5 comprising:
at least one lubricant base oil,
at least one detergent based on alkali or alkaline-earth metals, overbased
with metallic carbonate salts,
at least one neutral detergent,
10 0 a mixture of fatty amines comprising at least one fatty amine of formula (I)
RI-[NR~(CH~)~I~-NH~
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least 14 carbon atoms,
R2 represents a hydrogen atom or a -(CH&OH group,
the content by weight of fatty amine of formula (I) being greater than or
equal to 90% with respect to the total weight of the mixture of fatty
amines,
20 the fatty amine having a BN determined according to the standard ASTM
D-2896 ranging from 150 to 600 milligrams of potash per gram of amine,
the percentage by mass of fatty amine with respect to the total weight of
the lubricant being selected so that the BN provided by this compound
represents a contribution of at least 10 milligrams of potash per gram of
25 lubricant to the total BN of said cylinder lubricant and,
the percentage by mass of the overbased detergent with respect to the
total weight of the lubricant being selected so that the BN provided by the
metallic carbonate salts represents a contribution of at least 20 milligrams
of potash per gram of lubricant to the total BN of said cylinder lubricant.
30 2. Lubricant according to claim I in which the content by weight of fatty amine of
formula (I) is strictly less than 100% with respect to the total weight of the
mixture of fatty amines.
3. Cylinder lubricant according to claim I or 2 in which the content by weight of
fatty amine of formula (I) ranges from 90 to 99.9% with respect to the total
35 weight of the mixture of fatty amines.
4. Cylinder lubricant according to any one of the preceding claims having a BN
determined according to the standard ASTM D-2896 ranging from 50 to 100
milligrams of potash per gram of lubricant, preferably from 60 to 90 milligrams
of potash per gram of lubricant.
5 5. Cylinder lubricant according to any one of the preceding claims in which the
BN of the fatty amine determined according to the standard ASTM D-2896
ranges from 250 to 600 milligrams of potash per gram of amine, preferably
from 300 to 500 milligrams of potash per gram of amine.
6. Cylinder lubricant according to any one of the preceding claims in which the
10 percentage by mass of fatty amine with respect to the total weight of the
lubricant is selected so that the BN provided by this compound represents a
contribution of 10 to 60 milligrams of potash per gram of lubricant, more
preferentially from 10 to 30 milligrams of potash per gram of lubricant to the
total BN of said cylinder lubricant.
15 7. Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of fatty amine with respect to the total weight of the
lubricant is selected so that the BN provided by this compound represents at
least lo%, preferably 10 to 50%, more preferentially 10 to 30% of the total BN
of said cylinder lubricant.
20 8. Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of the mixture of fatty amines with respect to the total
weight of cylinder lubricant ranges from 2 to 10%.
9. Cylinder lubricant according to any one of the preceding claims in which R1
represents a linear or branched, saturated or unsaturated alkyl group
25 comprising from 14 to 22 carbon atoms, preferably from 16 to 20 carbon
atoms.
10. Cylinder lubricant according to any one of the preceding claims in which R2
represents a hydrogen atom.
I. Cylinder lubricant according to any one of the preceding claims in which the
30 mixture of fatty amines is presented in the form:
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched, saturated or unsaturated alkyl group comprising from 14 to 16
carbon atoms and R2 represents a hydrogen atom,
- of at least one fatty amine of formula (I) in which Rl represents a linear or
branched, saturated or unsaturated alkyl group comprising at least 18
carbon atoms and R2 represents a hydrogen atom,
and
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched, saturated or unsaturated alkyl group comprising at least 20
carbon atoms and R2 represents a hydrogen atom.
Cylinder lubricant according to any one of claims 1 to 10 in which the mixture
of fatty amines is presented in the form :
- of at least one fatty amine of formula (I) in which R, represents a linear or
branched unsaturated alkyl group comprising from 16 to 20 carbon atoms,
preferably from 18 to 20 carbon atoms and R2 represents a hydrogen
atom, and
- of at least one fatty amine of formula (I) in which R1 represents a linear or
branched saturated alkyl group comprising from 16 to 20 carbon atoms,
preferably from 18 to 20 carbon atoms and R2 represents a hydrogen
atom,
Cylinder lubricant according to any one of the preceding claims in which the
overbased and neutral detergents are selected from the carboxylates,
sulphonates, salicylates, naphthenates, phenates, and the mixed detergents
combining at least two of these types of detergents.
Cylinder lubricant according to any one of the preceding claims in which the
overbased and neutral detergents are compounds based on metals selected
from calcium, magnesium, sodium or barium, preferentially calcium or
magnesium.
Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of the overbased detergent with respect to the total
weight of the lubricant is selected so that the BN provided by the metallic
carbonate salts represents a contribution strictly greater than 20 to the total
BN of said cylinder lubricant.
Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of the overbased detergent with respect to the total
weight of the lubricant is selected so that the BN provided by the metallic
carbonate salts represents a contribution ranging from 30 to 70 milligrams of
potash per gram of lubricant to the total BN of said cylinder lubricant.
Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of the overbased detergent and of.the neutral detergent,
with respect to the total weight of lubricant, is selected so that the organic BN
provided by the detergent soaps represents a contribution of at least 10
milligrams of potash per gram of lubricant, preferentially ranging from 10 to 60
milligrams of potash per gram of lubricant, more preferentially from 10 to 40
milligrams of potash per gram of lubricant to the total BN of said cylinder
lubricant.
18. Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of the overbased detergent with respect to the total
5 weight of lubricant ranges from 8 to 30%, preferably from 10 to 30%.
19. Cylinder lubricant according to any one of the preceding claims in which the
percentage by mass of the neutral detergent with respect to the total weight of
lubricant ranges from 5 to 15%, preferably from 5 to 10%.
20. Cylinder lubricant according to any one of the preceding claims also
10 comprising an additional compound selected from:
- the primary, secondary or tertiary fatty monoalcohols, the alkyl chain of
which is linear or branched, saturated or unsaturated and comprising at
least 12 carbon atoms, preferentially from 12 to 24 carbon atoms, more
preferentially from 16 to 18 carbon atoms, advantageously the primary
15 monoalcohols with a saturated, linear alkyl chain,
- the esters of saturated fatty monoacids comprising at least 14 carbon
atoms and of alcohols comprising at most 6 carbon atoms, preferentially
the mono- and diesters, advantageously the monoesters of rnonoalcohols
and the diesters of polyols the ester functions of which are at a distance of
20 four carbon atoms at most, counting from the oxygen side of the ester
function.
21. Cylinder lubricant according to any one of the preceding claims, the kinematic
viscosity of which, measured according to the standard ASTM D445 at 100°C
ranges from 12.5 to 26.1 cSt, preferentially from 16.3 to 21.9 cSt.
25 22. Use of a cylinder lubricant according to any one of the preceding claims as a
single cylinder lubricant that can be used both with fuel oils with a sulphur
content of less than 1% by weight with respect to the total weight of the fuel oil
and with fuel oils with a sulphur content ranging from 1 to 3.5% by weight with
respect to the total weight of the fuel oil.
30 23. Use of a lubricant according to one of claims 1 to 21 in order to prevent
corrosion and/or reduce the formation of insoluble metallic salt deposits in twostroke
marine engines during the combustion of any type of fuel oil the sulphur
content of which is less than or equal to 3.5% by weight with respect to the
total weight of the fuel oil.
35 24. Additive concentrate for the preparation of cylinder lubricant having a BN
determined according to the standard ASTM D-2896 greater than or equal to
50 milligrams of potash per gram of lubricant, said concentrate having a BN
ranging from 100 to 400 mg KOHIg of concentrate, and comprising at least
one detergent based on alkali or alkaline-earth metals, overbased with metallic
carbonate salts, at least one neutral detergent and at least one fatty amine
having a BN ranging from 'l50 to 600 mg of potashlg of amine according to the
standard ASTM D-2896 and of formula (I):
5 RI-[NR~(CH~)~I~-NH~
(1)
in which:
R1 represents a linear or branched, saturated or unsaturated alkyl
group, comprising at least '14 carbon atoms,
R2 represents a hydrogen atom or a -(CH2)20H group,
the percentage by mass of said fatty amines in the concentrate being selected
so as to provide said concentrate with a BN contribution determined according
to the standard ASTM D-2896 ranging from 20 to 300 milligrams of potash per
gram of concentrate.