DESCRIPTION
5
CATALYST FOR PRODUCTION OF MONOCYCLIC AROMATIC
HYDROCARBONS AND METHOD OF PRODUCING MONOCYCLIC AROMATIC
HYDROCARBONS
TECHNICAL FIELD
'[0001]
The present invention relates to a catalyst for producing monocyclic aromatic
10 hydrocarbons and a method of producing monocyclic aromatic hydrocarbons, which are
capable of producing monocyclic aromatic hydrocarbons from oil containing a large
amount of polycyclic aromatic hydrocarbons.
Priority is claimed on Japanese Patent Application No. 2010-010262, filed
January 20, 2010, the content of which is incorporated herein by reference.
15
BACKGROUND ART
- - [0002]
Light cycle oil (hereinafter, referred to as "LCO"), which is cracked light oil
producedby a fluidized catalytic cracking, contains a large amount of polycyclic
20 aromatic hydrocarbons, and has been used as light oil or heavy oil. However, in recent
years, investigations have been conducted to obtain, from LCO, monocyclic aromatic
hydrocarbons having a carbon number of 6 to 8 (such as benzene, toluene, xylene and
ethylbenzene), which may be used as high-octane gasoline base materials or
petrochemical raw materials, and offer significant added value.
25 For example, Patent Document I to Patent Document 3 disclose methods of
2
producing monocyclic aromatic hydrocarbons from polycyclic aromatic hydrocarbons
contained in large amounts within LCO and the like by using zeolite catalysts.
[0003]
In addition, as a method of producing monocyclic aromatic hydrocarbons
5 through reaction using zeolite catalysts, Patent Document 4 discloses a method of
producing monocyclic aromatic hydrocarbons from aromatic compounds having a carbon
number of 9 or more by using beta-type zeolite, which has a 12-membered ring structure
and a large pore size, as a catalyst.
Patent Document 5 discloses a method of producing monocyclic aromatic
10 hydrocarbons from paraffin-based hydrocarbons having a carbon number of 2 to 12 by
using beta-type zeolite as a catalyst.
Citation List
Patent Document
15 [0004]
[Patent Document 1] Japanese Unexamined Patent Application, First
publication-No. H3=2128
[Patent Document 2] Japanese Unexamined Patent Application, First
publication No. H3-52993
20 [Patent Document 3] Japanese Unexamined Patent Application, First
publication No. H3-26791
[Patent Document 4] Published Japanese Translation No. H4-504577 of the
PCT International Publication
[Patent Document 5] Japanese Unexamined Patent Application, First
25 publication No. H2-184517
3
DISCLOSURE OF INVENTION
Technical Problem
[0005]
5 However, in the methods disclosed in Patent Document 1 to Patent Document 3,
the yields of monocyclic aromatic hydrocarbons having a carbon number of 6 to 8 have
not been entirely satisfactory. In addition, the methods disclosed in Patent Document 4
and Patent Document 5 are not methods of obtaining both monocyclic aromatic
hydrocarbons having a carbon number of 6 to 8 and aliphatic hydrocarbons having a
10 carbon number of 3 to 4 from feedstock in which a 10 vol% distillation temperature is
140°C or higher and a 90 vol% distillation temperature is 380°C or lower.
An object of the invention is to provide a catalyst for production of monocyclic
aromatic hydrocarbons and a method of producing monocyclic aromatic hydrocarbons,
which are capable of producing monocyclic aromatic hydrocarbons having a carbon
15 number of 6 to 8 from feedstock containing polycyclic aromatic hydrocarbons with high
yield.
Solution to Problem
[0006]
20 (1) According to an embodiment of the invention, a catalyst is provided for
production of monocyclic aromatic hydrocarbons having a carbon number of 6 to 8 from
feedstock in which a 10 vol% distillation temperature is 140°C or higher and a 90 vol%
distillation temperature is 380°C or lower. The catalyst contains crystalline
aluminosilicate including large-pore zeolite having a 12-membered ring structure, and
25 intermediate-pore zeolite having 10-membered ring structure.
4
(2) The catalyst for production of monocyclic aromatic hydrocarbons
according to (1), wherein in the crystalline aluminosilicate, a mass ratio of the large-pore
zeolite to the intermediate-pore zeolite (large-pore zeolite/intermediate-pore zeolite) is
preferably 2/98 to 50/50.
5 (3) The catalyst for production of monocyclic aromatic hydrocarbons
according to (1) or (2), wherein the large-pore zeolite is preferably a zeolite of any type
selected from a BEA type, an FAU type, and an MOR type.
(4) The catalyst for production of monocyclic aromatic hydrocarbons
according to any one of (1) to (3), wherein the large-pore zeolite is preferablyBEA-type
10 zeolite.
(5) The catalyst for production of monocyclic aromatic hydrocarbons
according to any one of (1) to (4), wherein the intermediate-pore zeolite is preferably
MFI-type zeolite.
(6) The catalyst for production of monocyclic aromatic hydrocarbons
15 according to any one of (1) to (5), wherein the catalyst preferably further contain
phosphorus.
(7) According to another embodiment-of-the invention, amethod is provided
of producing monocyclic aromatic hydrocarbons having a carbon number of 6 to 8. The
method includes bringing feedstock in which a 10 vol% distillation temperature is 140°C
20 or higher and a 90 vol% distillation temperature is 380°C or lower into contact with the
catalyst for production of monocyclic aromatic hydrocarbons according to any one of (1)
to (6).
(8) The method of producing monocyclic aromatic hydrocarbons having a
carbon number of 6 to 8 according to (7), wherein as the feedstock, light cycle oil
25 produced by a fluidized catalytic cracking is preferably used.
5
(9) The method of producing monocyclic aromatic hydrocarbons having a
carbon number of 6 to 8 according to (7) or (8), wherein the feedstock is preferably
brought into contact with the catalyst for production of monocyclic aromatic
hydrocarbons in a fluidized bed reaction unit.
5
Advantageous Effects of Invention
[0007]
According to the catalyst for production of monocyclic aromatic hydrocarbons
and the method of producing monocyclic aromatic hydrocarbons having a carbon number
10 of 6 to 8, monocyclic aromatic hydrocarbons having a carbon number of 6 to 8 is
preferably produced with high yield from feedstock in which a 10 vol% distillation
temperature is 140°C or higher and a 90 vol% distillation temperature is 380°C or lower.
BEST MODE FOR CARRYING OUT THE INVENTION
15 [0008]
(Catalyst for Production of Monocyclic Aromatic Hydrocarbon)
The catalyst for production of monocyclie aromatic`h rocarbons according
this embodiment (hereinafter, abbreviated as "catalyst") is used for producing
monocyclic aromatic hydrocarbons having a carbon number of 6 to 8 (hereinafter,
20 abbreviated as "monocyclic aromatic hydrocarbons") from feedstock containing
polycyclic aromatic hydrocarbons and saturated hydrocarbons, and contains crystalline
aluminosilicate.
[0009]
(Crystalline Aluminosilicate)
25 In this embodiment, the crystalline aluminosilicate contains large-pore zeolite
6.
having a 12-membered ring structure, and intermediate-pore zeolite having a
10-membered ring structure.
As the large-pore zeolite having a 12-membered ring structure, for example,
zeolites having a framework type of an AFT type, an ATO type, a BEA type, a CON type,
5 an FAU type, a GME type, an LTL type, an MOR type, an MTW type, and an OFF type
is preferably exemplified. Among these, the BEA type, the FAU type, and the MOR
type are preferable from an industrially usable aspect, and the BEA type is more
preferable because the yield of the monocyclic aromatic hydrocarbons having a carbon
number of 6 to 8 is relatively raised.
10 As the intermediate-pore zeolite having a 10-membered ring structure, for
example, zeolites having a framework type of an AEL type, an EUO type, an FER type,
an HEU type, an MEL type, an MFI type, an NES type, a TON type, and a WEI type is
preferably exemplified. Among these, the MFI type is preferable because the yield of
the monocyclic aromatic hydrocarbons having a carbon number of 6 to 8 is relatively
15 raised.
In addition, all of the framework type types of the zeolite , which are exemplified
in this- embodiment are structure codes based on thezlefinitior ofthu-lnWrnational
Zeolite Association.
[0010]
20 In addition to the large -pore zeolite, the crystalline aluminosilicate may contain
small-pore zeolite having a stricture of a 10-membered ring or less, and ultra-large-pore
zeolite having a structure of a 14-membered ring or more.
Here, as the small-pore zeolite, for example, zeolites having a framework type of
an ANA type, a CHA type, an ERI type, a GIS type, a KFI type, an LTA type, an NAT
25 type, a PAU type, and a YUG type is preferably exemplified.
7
As the ultra-large-pore zeolite, for example, zeolites having a framework type of
a CLO type, and a VPI type is preferably exemplified.
[0011]
In a case where the catalyst is used as a catalyst for a fixed bed, the content of
5 the crystalline aluminosilicate is preferably 60 to 100 % by mass on the basis of 100 %
by mass of the entirety of the catalyst, and more preferably 70 to 100 % by mass, and still
more preferably 90 to 100 % by mass. When the content of the crystalline
aluminosilicate is 60 % by mass or more, the total yield of the monocyclic aromatic
hydrocarbons having a carbon number of 6 to 8 and the aliphatic hydrocarbons having a
10 carbon number of 3 to 4 is sufficiently raised.
In a case where the catalyst is used as a catalyst for a fluidized bed, the content
of the crystalline aluminosilicate is preferably 20 to 60 % by mass on the basis of 100 %
by mass of the entirety of the catalyst, and more preferably 30 to 60 % by mass, and still
more preferably 35 to 60 % by mass. When the content of the crystalline
15 aluminosilicate is 20% by mass or more, the total yield of the monocyclic aromatic
hydrocarbons having a carbon number of 6 to 8 and the aliphatic hydrocarbons having a
carbon-number-of 3 to 4 is sufficiently raised. When-the content of the--crystalline
aluminosilicate exceeds 60 % by mass, the content of a binder that may be mixed with
the catalyst becomes small, and thus may be not appropriate as the catalyst for the
20 fluidized bed.
[0012]
In the crystalline aluminosilicate, a mass ratio of the large-pore zeolite to the
intermediate-pore zeolite (large-pore zeolite/intermediate-pore zeolite) is preferably 2/98
to 50/50, more preferably 5/95 to 50/50, still more preferably 10/90 to 30/70. When the
25 mass ratio is 2/98 or more, an effect of using the large-pore zeolite is sufficiently
8
exhibited, and thus the yield of the monocyclic aromatic hydrocarbons is sufficiently
raised. When the mass ratio is 50/50 or less, coking of the feedstock is prevented, and
thus the yield of the monocyclic aromatic hydrocarbons is sufficiently raised.
[0013]
5 (Other Components)
The catalyst may contain gallium and/or zinc as necessary. When gallium
and/or zinc are contained, a generation ratio of the monocyclic aromatic hydrocarbons
haying a carbon number of 6 to 8 tends to be increased.
[0014]
10 As a method used to incorporate gallium into the catalyst, a type in which
gallium is incorporated in a lattice framework of the crystalline aluminosilicate
(crystalline aluminogallosilicate), a type in which gallium is carried by the crystalline
aluminosilicate (gallium-supporting crystalline aluminosilicate), and a type including
both of these types is exemplified.
15 As a method used to incorporate zinc into the catalyst, a type in which zinc is
incorporated in a lattice framework of the crystalline aluminosilicate (crystalline
aluminozincosilicate), a typeinwhich zinc is carried-bythe crystalline aluminosilicate
(zinc-supporting crystalline aluminosilicate), and a type including both of these types is
exemplified.
20 The crystalline aluminogallosilicate and the crystalline aluminozincosilicate
have a structure in which SiO4 , A1O4, and GaO4/ZnO4 structures have a tetrahedral
coordination in a framework. In addition, the crystalline aluminogallosilicate and the
crystalline aluminozincosilicate may be obtained , for example, by gel crystallization
through hydrothermal synthesis , by a method in which gallium or zinc is inserted into the
25 lattice framework of the crystalline aluminosilicate, or by a method in which aluminum is
9
inserted into the lattice framework of crystalline gallosilicate or crystalline zincosilicate.
The gallium-supporting crystalline aluminosilicate may be obtained by
supporting gallium on a crystalline aluminosilicate using a conventional method such as
an ion-exchange method or impregnation method. There are no particular limitations
5 on the gallium source used in these methods, and examples include gallium salts such as
gallium nitrate and gallium chloride, and gallium oxide.
The zinc-supporting crystalline aluminosilicate may be obtained by supporting
zinc on a crystalline aluminosilicate using a known method such as an ion-exchange
method or impregnation method. There are no particular limitations on the zinc source
10 used in these methods, and examples include zinc salts such as zinc nitrate and zinc
chloride, and zinc oxide.
[0015]
In a case where the catalyst contains gallium and/or zinc, the lower limit of the
content of gallium and/or zinc is preferably 0.01 % by mass or more on the basis of
15 100 % by mass of the total mass of the crystalline aluminosilicate, and more prefer