CATALYST FOR IMPROVING COLD FLOW PROPERTIES OF VEGETABLE OIL DERIVED HYDROCARBONS
FIELD OF THE INVENTION
[0001] The present invention generally relates to hydro isomerization of saturated hydrocarbons. More particularly, the present disclosure provides a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products. Aspects of the present disclosure also provide a process for preparation of a catalyst composition that finds utility in conversion of vegetable oil derived diesel range hydrocarbons to isomerized products. Aspects of the present disclosure also provide a process for conversion of paraffin to isomerized products thereof utilizing the catalyst composition of the present invention.
BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Use of renewable feed stocks for production of transportation fuels as a substitute to depleting fossil fuel is increasing. European Union (EU) targets 2050 to use maximum bio-oil in transportation fuel. Asian countries also set a target of 20% blending of bio-fuels by 2020. Bio-fuels will account for 9% of global transport fuels by 2030 with their production increasing three and half times from 1.8mbpd in 2010 to 6.7 mbpd by 2030. Vegetable oils are a renewable resources currently being used for production of bio-fuels from sustainable biomass feed stocks. There are many benefits of bio-fuels apart from their use as domestic fuels like decrease in greenhouse gas emissions, dependence on fossil fuels, enhancing rural economy and increased national security. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of bio-fuels from vegetable oils. This process has many benefits; however, new biodiesel plants must be built requiring a capital investment. The economics of biodiesel production depend on selling by-product glycerol, and increased biodiesel production will cause the price for glycerol to decrease. Other alternative for bio-fuels production is hydroprocessing of vegetable oils. One advantage for this 2
process is to use existing petroleum refineries configuration for the process. There is no problem of glycerol production and its disposal.
[0004] In refining industry hydrotreating is used to remove S, N and metals from petroleum-derived feed stocks including heavy gas-oil or vacuum gas-oil. Vegetable oil hydrotreating produces straight chain alkanes ranging from n-C15–n-C18 which have a high cetane number ranging from 75-98, whereas typical diesel fuel has a cetane number around 45. The normal alkanes produced also have better cold flow properties. Commercial road trial of six postal delivery vans for a period of ten months showed that engine fuel economy was greatly improved by 20% blend of hydrotreated tall oil with diesel [M. Stumborg, A. Wong, E. Hogan, Bioresour. Technol. 56 (1996) 13]. The advantages of hydrotreated vegetable oil over trans-esterification resulted switch over from fossil fuel to vegetable oil without any hardware modification in refinery and motor engine in transportation sector [M. Stumborg, A. Wong, E. Hogan, Bioresour. Technol. 56 (1996) 13]. Neste Oil Corporation is currently adding 3500 barrels per day unit to their Porvoo Kilpilahti, Finland oil-refinery that produces diesel fuel from vegetable oil by a modified hydrotreating process. To process vegetable oil in existing petroleum refinery using existing infrastructure to convert vegetable oil to diesel fuel using vegetable oils need to be co-processed with petroleum-derived feed stocks such as heavy vacuum oil (HVO).
[0005] Loewenstein et al. in US patent 8,877,669 discloses use of hydroisomerization catalysts for processing a bio-based feedstock into biodiesel fuels. These catalysts comprise a catalytic material and a matrix component. The catalytic material is made up of a molecular sieve ZSM-23. However, the efficacy of catalyst was found to be far from satisfactory.
[0006] Hanks et al. in US patent 874160 discloses that feeds containing a hydrotreated biocomponent portion, and optionally a mineral portion, can be processed under catalytic conditions for isomerization and/or dewaxing. The sulfur content of the feed for dewaxing can be selected based on the hydrogenation metal used for the catalyst. Diesel fuel products with improved cold flow properties can be produced. In this patent usage of molecular sieves such as Beta, USY, ZSM-5, ZSM-35, ZSM-23, ZSM-48 is described. However, the efficacy of catalyst was found to be far from satisfactory.
[0007] U.S. Patent 5,233,109 describes the implementation of thermal or catalytic cracking of vegetable oils leading to a wide range of products such as paraffins, but also aromatic derivatives and unsaturated derivatives in the boiling range of gasoline and gas oils. This method produces derivatives that cannot be directly used as gas oil fuel because it is not meeting specification like oxidation 3
stability. Different catalysts used for the conversion are Akzo Ketjen Vison-47, Zeolite X, silica gel and Fluka alumina.
[0008] US patent 7,803,269 discloses a process for improving the cold flow properties of a hydrocarbon stream employing a substantially liquid-phase continuous hydroisomerization zone where the reaction zone has a substantially constant level of dissolved hydrogen without the addition of additional hydrogen to the reaction zone. A noble metal on acidic support is claimed for hydroisomerization catalyst but no details about support and metal concentrations were revealed in the patent.
[0009] US patent 7781629 teaches a hydrotreating method where two catalyst beds were used by dedicating first one for only hydrodesulphurization where as second one is used for treating the some part of the conventional gas oil and vegetable oils together. The effluents obtained at the outlet of the second catalyst bed can be mixed with the predominant stream from the first bed. By following this method the process economy and specifications of the products were greatly met. CoMo and NiMo catalysts were used in the process but concentrations of metals were not given. Further, the patent is silent on issues of cold flow properties.
[00010] In the US patent 5,705,722, a commercial nickel-molybdenum or alumina catalyst available under the trade mark CRITERION 424, was supplied in the form of extrudates was used for vegetable oil conversion. US20070260102 discloses a process where vegetable oils are converted to paraffins, wherein vegetable oils are hydrotreated as such or in combination with mineral hydrocarbon oil. This application also concentrated in producing the n-paraffins which are raw materials for the production of detergents (LAB) which are beneficial to use in situation where kerosene is limiting factor for producing n-paraffins.
[00011] US patent no. 2163563 teaches a method for conversion of vegtetable oils and mineral oil mixtures in presence of hydrogen at high pressures (5-50Mpa) using reduced nickel catalysts supported on alumina. Current invention mainly deals with hydroisomerization of hydrotreated vegetable oils.
[00012] There is, therefore, a need for improved catalyst and method of use thereof for hydroisomerization of diesel range hydrocarbons which are derived from hydrotreatment of vegetable oils. The present disclosure generally satisfies the existing needs and overcomes the one or more drawbacks associated with conventional catalysts and methods of hydroisomerization of diesel range hydrocarbons derived from hydrotreatment of vegetable oils.
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OBJECTS OF THE INVENTION
[00013] Primary object of the present invention to provide a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof.
[00014] Another object of the present invention is to provide a method for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof.
[00015] Another object of the present invention to provide a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof that is easy to prepare.
[00016] Another object of the present invention to provide a method of preparation of a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof.
[00017] Another object of the present invention to provide a method of preparation of a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products that is economical.
[00018] Another object of the present invention to provide a method of preparation of a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products that improves the cold flow properties.
[00019] Other objects of the present invention will be apparent from the description of the invention herein below.
SUMMARY OF THE INVENTION
[00020] The present invention generally relates to hydroisomerization of saturated hydrocarbons. More particularly, the present disclosure provides a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products. Aspects of the present disclosure also provide a process for preparation of a catalyst composition that finds utility in conversion of vegetable oil derived diesel range hydrocarbons to isomerized products. Aspects of the present disclosure also provide a process for conversion of paraffin to isomerized products thereof utilizing the catalyst composition of the present invention.
[00021] An aspect of the present disclosure provides a catalyst composition to effect conversion of hydrotreated vegetable oils to isomerized hydrocarbons, the catalyst composition comprising: (a) an inorganic oxide based porous support in an amount ranging from about 80% to about 99.9% by weight 5
of the composition, wherein said inorganic oxide based porous support comprises: alumina in an amount of at least 25% by weight of the inorganic oxide, and the remainder being silica; and (b) at least one noble metal in an amount ranging from about 0.1% to about 10% by weight of the composition. In an embodiment, the inorganic oxide based porous support is selected from any or a combination of ZSM-5, HY zeolite, SAPO-11 zeolite, HY zeolite and regenerated refinery spent lobs catalyst. In an embodiment, the inorganic oxide based porous support exhibits pore volume ranging from about 0.25cc/g to about 0.95cc/g. In an embodiment, the inorganic oxide based porous support exhibits surface area ranging from about 100m2/g to about 700m2/g. In an embodiment, the inorganic oxide based porous support exhibits unimodal pore size distribution with pores ranging from about 20Å to about 500Å. In an embodiment, the inorganic oxide based porous support exhibits unimodal pore size distribution with average pore size ranging from about 20Å to about 100Å. In an embodiment, the catalyst composition comprises the at least one noble metal in an amount ranging from about 0.1% to about 1% by weight of the composition. In an embodiment, the noble metal is Platinum.
[00022] In an embodiment, the inorganic oxide based porous support comprises about 20.8% of silica and about 79.2% of alumina. In an embodiment, the inorganic oxide based porous support exhibits unimodel pore size distribution ranging from about 20Å to about 150Å, surface area of about 371 m2/g and pore volume of about 0.80 cc/g.
[00023] In an embodiment, the inorganic oxide based porous support comprises about 40.2% of silica and about 59.8% of alumina. In an embodiment, the inorganic oxide based porous support exhibits unimodel pore size distribution ranging from about 20Å to about 250Å, surface area ranging from about 400m2/g to about 500m2/g, bulk density ranging from about 0.80 to about 0.85 g/cc and pore volume of about 0.83cc/g.
[00024] In an embodiment, the inorganic oxide based porous support is the regenerated refinery spent lobs catalyst, wherein the regenerated refinery spent lobs catalyst exhibits surface area ranging from about 200 m2/g to about 250 m2/g and pore volume ranging from about 0.4 cc/gram to about 0.6 cc/gram. In an embodiment, the regenerated refinery spent lobs catalyst is prepared by subjecting a refinery spent lobs catalyst, with pore size ranging from about 20Å to about 150Å and with average pore size of about 47Å, to solvent extraction to remove any trapped hydrocarbons therefrom, followed by calcinations thereof by heating in any of (a) air or (b) 2.5% O2 in N2, at the rate of 2oC/minute at a temperature of about 540oC for 4 hours to effect complete removal of carbon therefrom.
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[00025] In an embodiment, the inorganic oxide based porous support is ZSM-5 and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.41cc/g, surface area of about 351m2/g and average pore size of about 48Å.
[00026] In an embodiment, the inorganic oxide based porous support is HY zeolite and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.31cc/g, surface area of about 623m2/g and average pore size of about 20Å.
[00027] In an embodiment, the inorganic oxide based porous support is SAPO-11 zeolite and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.25cc/g, surface area of about 108m2/g and average pore size of about 91Å.
[00028] Another aspect of the present disclosure relates to a method for preparation of a catalyst composition to effect conversion of hydrotreated vegetable oils to isomerized hydrocarbons, the method comprising the steps of: effecting drying of a pre-determined amount of an inorganic oxide based porous support by heating it in a reactor at about 500°C in air for about 4 hours; effecting loading of at least one noble metal onto said inorganic oxide based porous support, wherein said loading is effected by any of equilibrium adsorption method and wet impregnation method, and wherein said loading is effected at a room temperature; effecting drying of said noble metal loaded inorganic oxide based porous support by heating at a temperature ranging from about 110°C to about 120°C and for a time period ranging from about 8 hours to about 16 hours; and effecting calcinations of the dried noble metal loaded inorganic oxide based porous support at a temperature ranging from about 450°C to 550°C for a time period ranging from about 3 hours to about 4 hours.
[00029] Another aspect of the present disclosure relates to a process of conversion of paraffin to isomerized products thereof, the process comprising the step of contacting the catalyst composition as realized in embodiments of the present disclosure with paraffin at a pre-determined pressure, and temperature. In an embodiment, the process comprises the step of contacting the catalyst composition with paraffin at a hydrogen pressure of about 20bar and at a temperature of about 340°C.
BRIEF DESCRIPTION OF DRAWINGS
[00030] The diagrams are for illustration only, which thus is not a limitation of the present invention, and wherein:
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[00031] FIG. 1 illustrates an exemplary graph depicting pore size distribution of inorganic oxide based porous support, in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[00032] The embodiments herein and the various features and advantageous details thereof are explained more comprehensively with reference to the non-limiting embodiments that are detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein.
[00033] Unless otherwise specified, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions may be included to better appreciate the teaching of the present invention.
[00034] As used in the description herein, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[00035] As used herein, the terms “comprise”, “comprises”, “comprising”, “include”, “includes”, and “including” are meant to be non- limiting, i.e., other steps and other ingredients which do not affect the end of result can be added. The above terms encompass the terms “consisting of” and “consisting essentially of”.
[00036] As used herein, the terms “composition” “blend,” or “mixture” are all intended to be used interchangeably.
[00037] The terms “weight percent,” “wt-%,” “percent by weight,” “% by weight,” and variations thereof, as used herein, refer to the concentration of a substance as the weight of that substance divided by the total weight of the composition and multiplied by 100. It is understood that, as used here, “percent,” “%,” and the like are intended to be synonymous with “weight percent,” “wt-%,” etc.
[00038] The present invention generally relates to hydroisomerization of saturated hydrocarbons. More particularly, the present disclosure provides a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products. Aspects of the present disclosure also provide a process for preparation of a catalyst composition that finds utility in conversion of vegetable oil derived diesel range hydrocarbons to isomerized products. Aspects of the present disclosure also
8
provide a process for conversion of paraffin to isomerized products thereof utilizing the catalyst composition of the present invention.
[00039] The basic principle behind the hydroisomerization of saturated hydrocarbons is to mix the VGO stream with vegetable oil and by effect of high pressure, high temperature and bifunctional catalyst, the triglycerides in the oil are transformed into hydrocarbons in the diesel range. Hydrotreating catalyst is a transition metal supported on inorganic material. Catalyst is sulfided prior to hydrotreating to convert the metal oxides to active sulfided form. During the process of sulfidation, coordinatively unsaturated sites (CUS) are created and these active sites are responsible for hydrotreating reactions. Generally, hydrotreating conditions are temperatures ranging from 320°C to 370°C and hydrogen pressures ranging from 35 to 50 bar and LHSV ranging from 1 to 1.5 H-1. In vegetable oil hydrotreating process, the metal function of the catalyst and a high hydrogen pressure contribute to the saturation of the side chains of the triglycerides. The acid function of the catalyst contributes to the cracking of the C-O bond and to the isomerization of the n-olefins formed, which are then transformed to isoparaffins. Optimum high temperature is important to increase the cracking activity. However, at temperatures higher than 380°C, cracking of the hydrocarbons increases and hence, the yield of diesel decreases. Though more gasoline and propane can be obtained in this way, depending on the refinery requirements, they may also be desirable products. The hydrocarbon mixture produced from the hydrotreating or hydrocracking of vegetable oil is commonly called green diesel, as it is indeed diesel but produced from a green plants. Green diesel is mainly composed of n-heptadecane and n-octadecane. As both of them contain a high cetane number, green diesel can also be used as a cetane additive. A green diesel with high content of isoparaffins is desirable as they have lower pour point than those of the corresponding n-paraffins. The quantum of isoparaffins from vegetable oil hydroconversion activity depends on the acidity of the catalyst. Thus, one needs to select suitable operating conditions and catalysts to obtain maximum yield of high quality green diesel.
[00040] Chemistry of vegetable oils hydroconversion is explained in US9034782, the contents of which are incorporated herein in its entirety. Often the green diesel obtained by hyroprocessing route is with high pour point. To meet the diesel specification the pour point need to be reduced to the desired levels. The green diesel which was obtained in hydroconversion of vegetable oils need further treatment which is hydroisomeriztion.
[00041] Hydroisomeriation is generally carried out over bifunctional catalysts, which possess both hydrogenation and acidic properties. The metallic sites are responsible for dehydrogenation of n-
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paraffins to corresponding olefins followed by hydrogenation of iso-olefins to corresponding isoparaffins, while acidic sites achieve skeletal isomerization of olefins via carbenium ion. High hydrogenation activity and a low acidity are required for maximizing hydroisomerization versus hydrocracking. A balance is required between hydrogenation functionality and acidity to obtain high isomerization selectivity for long-chain paraffins.
[00042] Accordingly, an aspect of the present disclosure provides a catalyst composition to effect conversion of hydrotreated vegetable oils to isomerized hydrocarbons, the catalyst composition comprising: (a) an inorganic oxide based porous support in an amount ranging from about 80% to about 99.9% by weight of the composition, wherein said inorganic oxide based porous support comprises: alumina in an amount of at least 25% by weight of the inorganic oxide, and the remainder being silica; and (b) at least one noble metal in an amount ranging from about 0.1% to about 10% by weight of the composition. In an embodiment, the inorganic oxide based porous support is selected from any or a combination of ZSM-5, HY zeolite, SAPO-11 zeolite, HY zeolite and regenerated refinery spent lobs catalyst.
[00043] In an embodiment, the inorganic oxide based porous support exhibits pore volume ranging from about 0.25cc/g to about 0.95cc/g. In an embodiment, the inorganic oxide based porous support exhibits surface area ranging from about 100m2/g to about 700m2/g. In an embodiment, the inorganic oxide based porous support exhibits unimodal pore size distribution with pores ranging from about 20Å to about 500Å. In an embodiment, the inorganic oxide based porous support exhibits unimodal pore size distribution with average pore size ranging from about 20Å to about 100Å.
[00044] In an embodiment, the catalyst composition comprises the at least one noble metal in an amount ranging from about 0.1% to about 1% by weight of the composition. In an embodiment, the noble metal is Platinum.
[00045] In an embodiment, the inorganic oxide based porous support comprises about 20.8% of silica and about 79.2% of alumina. In an embodiment, the inorganic oxide based porous support exhibits unimodel pore size distribution ranging from about 20Å to about 150Å, surface area of about 371 m2/g and pore volume of about 0.80 cc/g.
[00046] In an embodiment, the inorganic oxide based porous support comprises about 40.2% of silica and about 59.8% of alumina. In an embodiment, the inorganic oxide based porous support exhibits unimodel pore size distribution ranging from about 20Å to about 250Å, surface area ranging from about 400m2/g to about 500m2/g, bulk density ranging from about 0.80 to about 0.85 g/cc and 10
pore volume of about 0.83cc/g. FIG. 1 illustrates an exemplary graph depicting pore size distribution of inorganic oxide based porous support with about 0.5% platinum leaded thereon (that include about 40.2% of silica and about 59.8% of alumina), in accordance with an embodiment of the present disclosure.
[00047] In an embodiment, the inorganic oxide based porous support is the regenerated refinery spent lobs catalyst, wherein the regenerated refinery spent lobs catalyst exhibits surface area ranging from about 200 m2/g to about 250 m2/g and pore volume ranging from about 0.4 cc/gram to about 0.6 cc/gram. In an embodiment, the regenerated refinery spent lobs catalyst is prepared by subjecting a refinery spent lobs catalyst, with pore size ranging from about 20Å to about 150Å and with average pore size of about 47Å, to solvent extraction to remove any trapped hydrocarbons therefrom, followed by calcinations thereof by heating in any of (a) air or (b) 2.5% O2 in N2, at the rate of 2oC/minute at a temperature of about 540oC for 4 hours to effect complete removal of carbon therefrom.
[00048] In an embodiment, the inorganic oxide based porous support exhibits pore volume of about 0.83cc/g, surface area of about 464 m2/g, unimodal pore size distribution with pores having size ranging from about 20Å to about 300Å, and with average pore size of about 75Å.
[00049] In an embodiment, the inorganic oxide based porous support exhibits pore volume of about 0.93cc/g, surface area of about 408m2/g, unimodal pore size distribution with pores having size ranging from about 20Å to about 200Å, and with average pore size of about 87Å.
[00050] In an embodiment, the inorganic oxide based porous support exhibits pore volume of about 0.80cc/g, surface area of about 371m2/g.
[00051] In an embodiment, the inorganic oxide based porous support exhibits pore volume of about 0.76cc/g, surface area of about 305m2/g.
[00052] In an embodiment, the inorganic oxide based porous support exhibits pore volume of about 0.65cc/g, surface area of about 215m2/g.
[00053] In an embodiment, the inorganic oxide based porous support is ZSM-5 and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.41cc/g, surface area of about 351m2/g and average pore size of about 48Å.
[00054] In an embodiment, the inorganic oxide based porous support is HY zeolite and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.31cc/g, surface area of about 623m2/g and average pore size of about 20Å.
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[00055] In an embodiment, the inorganic oxide based porous support is SAPO-11 zeolite and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.25cc/g, surface area of about 108m2/g and average pore size of about 91Å.
[00056] Another aspect of the present disclosure relates to a method for preparation of a catalyst composition to effect conversion of hydrotreated vegetable oils to isomerized hydrocarbons, the method comprising the steps of: effecting drying of a pre-determined amount of an inorganic oxide based porous support by heating it in a reactor at about 500°C in air for about 4 hours; effecting loading of at least one noble metal onto said inorganic oxide based porous support, wherein said loading is effected by any of equilibrium adsorption method and wet impregnation method, and wherein said loading is effected at a room temperature; effecting drying of said noble metal loaded inorganic oxide based porous support by heating at a temperature ranging from about 110°C to about 120°C and for a time period ranging from about 8 hours to about 16 hours; and effecting calcinations of the dried noble metal loaded inorganic oxide based porous support at a temperature ranging from about 450°C to 550°C for a time period ranging from about 3 hours to about 4 hours. In an embodiment, the loading of at least one noble metal onto the inorganic oxide based porous support is effected by wet impregnation method.
[00057] Another aspect of the present disclosure relates to a process of conversion of paraffin to isomerized products thereof, the process comprising the step of contacting the catalyst composition as realized in embodiments of the present disclosure with paraffin at a pre-determined pressure, and temperature. In an embodiment, the process comprises the step of contacting the catalyst composition with paraffin at a hydrogen pressure of about 20bar and at a temperature of about 340°C.
[00058] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
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EXAMPLE
EXAMPLE 1
[00059] Hydroisomerization catalysts were prepared by using commercially available porous, high surface area silica-alumina extrudates (the inorganic oxide based support) with an average diameter in the range of 1 to 1.5 mm and length in the range of 3-7 mm. The support material was observed to contain unimodal pore size distribution having majority of the pores in the range of 20-250Å. Four different silica-alumina supports were used with different silica-alumina ratios. The above support material was dried at 500°C in air for 4 hours. Dried support was deposited with required amount of hexa chloro platinic acid using impregnation method for obtaining the noble metal concentration of about 0.3wt%. The final product was dried at 110oC for 10-14 hours and calcined at 540oC for 4 hours. These samples are referred to as catalyst-1, catalyst-2, catalyst-3 and catalyst-4 respectively in the Table 1 provided hereinbelow –
Table 1: Properties of Catalysts 1 through 6
Catalyst Reference No.
SiO2
wt% of inorganic oxide support
Al2O3
wt% of inorganic oxide support
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Conversion
%
Selectivity
%
Pour point, °C
Catalyst 1
40.2
59.8
464
0.83
0.3
78.6
62.4
-21
Catalyst 2
29.8
70.2
408
0.93
0.3
35.2
66.3
-6
Catalyst 3
20.8
79.2
371
0.80
0.3
62.7
92.0
-9
Catalyst 4
5
95
130
0.12
0.3
6.5
77.5
-5
Catalyst 5
1.5
98.5
227
0.22
0.3
3.4
43.2
-5
[00060] The hydroisomerization activity of the catalysts was evaluated by high pressure and high temperature batch reactor studies. In batch reactor studies, the catalysts were first reduced in a separate continuous reactor at 350°C under flow of H2 (100 mL/min) for 3 h. After reduction, the reactor was cooled to room temperature and the catalyst was quickly transferred to a 500 mL Parr reactor, loaded with hexadecane/hydroterated jatropha oil (HJO) feed. After the reaction, the vessel was cooled and de-pressurized. The product was separated by filtration and analyzed by gas chromatography, pour point and SIMDIS analysis. Conversion and selectivity were analyzed and calculated by gas chromatography of the liquid yield obtained (VLY).
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[00061] From the table 1, it can be observed that catalyst 1 exhibit highest conversion followed by Catalyst 3. However, catalyst 3 exhibited highest selectivity of 92% for isomerized products when compared to Catalyst 1. Pour points obtained for these catalysts were also found to be good. Particularly, catalyst 1 and catalyst 3 meet the required specifications of pour point.
EXAMPLE 2
[00062] Al-MCM-41 was prepared by hydrothermal synthesis route. 2.67g of sodium hydroxide was dissolved in 147g of distilled water. 5.95g of cetyltrimethyl ammonium bromide (CTAB) was added to it and stirred for 1h to get a homogeneous solution. Then, Tetra ethyl orthosilicate (TEOS) was added drop wise over 30-45 min, aluminosilicate was added to it and stirring was continued for another 1h. The pH of the slurry was adjusted to 9.5 using a 4N sulphuric acid solution. The resultant gel was stirred for 6 h, transferred to a Teflon-lined stainless-steel autoclave and subjected to hydrothermal synthesis at 373 K for 48 h. The solid formed was filtered, washed and dried at 373 K and then, calcined at 823 K for 6 h to remove the template molecules. Platinum is impregnated (loaded) on Al-MCM-41 support. The final product was dried at 110o C for overnight and calcined at 540o C for four hours. This sample is referred to as catalyst 6 in Table 2, provided hereinbelow.
Table 2: Properties of Catalyst 6
Catalyst Reference No.
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Conversion
%
Selectivity
%
Pour point, °C
Catalyst 6
464
0.83
0.3
11.3
13.4
18
[00063] Catalyst 6 was found not to be selective for hydroisomerization. Further, the pour point was found to be high.
EXAMPLE 3
[00064] ZSM-5 was prepared and used as catalyst support (inorganic oxide support). ZSM-5 was prepared using the following gel composition -
[00065] Gel composition: SiO2: 0.01 Al2O3: 0.25 TPAOH: 0.05 Na2O : 30 H2O
[00066] For the preparation of ZSM-5, 10.415g TEOS was added to a Flat bottom RB containing 20ml water and 12.706 g 20% Tetra propyl ammonium hydroxide (TPAOH) and stirred overnight at 70oC. Solution 2 was prepared by dissolving 0.375g Al(NO3)3 and 0.2g NaOH in 2ml 14
water. Solution 2 was then added to solution 1 drop wise and mixture was stirred for another 1-2 hours. The resultant gel was transferred to a Teflon-lined stainless-steel autoclave and subjected to hydrothermal synthesis at 473 K for 36 h. The solid formed was filtered, washed and dried at 373 K and then, calcined at 823 K for 6 h to remove the template molecules. The above support material was dried at 500°C in air for 4 Hrs. Dried support was deposited/loaded with desired amount of hexa chloro platonic acid using impregnation method. The final product was dried at 110oC for 10-14 hours and calcined at 540oC for 4 hours. This catalyst is referred to as Catalyst-7 in the Table 3, provided hereinbelow. Hydroconversion studies were carried out in a high pressure batch reactor as per the procedure explained in the example 1.
Table 3: Properties of Catalyst 7
Catalyst Reference No.
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Conversion
%
Selectivity
%
Pour point, °C
Catalyst 6
335
0.4
0.5
85.8
0.8
-9
[00067] Catalyst 7 exhibited good pour point. However, selectivity was found to be very poor.
EXAMPLE 4
[00068] SAPO-11 was used as support. SAPO 11 was prepared as per the following procedure.
[00069] Gel composition - 0.2 SiO2: Al2O3 : P2O5 : DPA : 50 H2O
[00070] For the preparation of SAPO-11, 10g Catapal (70% Al2O3) and 15.824g orthophosphoric acid (85%) was added to 61.76 mL water and stirred for 1h. Then 6.945g DPA followed by TEOS was added drop wise and stirred for 3-4h. The resultant gel was transferred to a Teflon-lined stainless-steel autoclave and subjected to hydrothermal synthesis at 473 K for 24 h. The solid formed was filtered, washed and dried at 373 K and then, calcined at 873 K for 6 H to remove the template molecules. 0.5% platinum is impregnated on dried support. Hydroisomerization reaction was carried out as per the procedure explained in Example-1 and the results are tabulated in Table 4.
Table 4: Properties of Catalyst 8
Catalyst Reference No.
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Conversion
%
Selectivity
%
Pour point, °C
15
Catalyst 8
300
0.34
0.5
51.4
61.9
5
[00071] Catalyst 8 exhibited pour point that need to be reduced further.
EXAMPLE 5
[00072] Y zeolite was prepared and used as support for noble metal. Zeolite Y was prepared by seed gel method as provided hereinbelow -
[00073] Seed Gel (5% of Al): 10.67 Na2O : Al2O3 :10 SiO2 : 180 H2O
[00074] Feed Stock Gel (95% of Al): 4.30 Na2O : Al2O3 : 10 SiO2:180 H2O
[00075] Over all Gel: 4.62 Na2O : Al2O3 : 10 SiO2 : 180 H2O
Seed gel preparation
[00076] 1.662g water, 0.339 g NaOH and 0.174g sodium aluminate were mixed and stirred to get clear solution. 1.883g sodium silicate solution was added and stirred for 1h and then aged for 24h at RT in polypropylene bottle.
Stock solution
[00077] 21.8g water, 0.023 g NaOH and 2.18g sodium aluminate were mixed and stirred to get clear solution. To this 23.73g sodium silicate solution was added and stirred to get a smooth gel.
[00078] To this gel, seed gel was added slowly and stirred for 1h. The resultant gel was transferred to a polypropylene bottle and aged at 373 K for 6 h. The solid formed was filtered, washed and dried at 373 K and then, calcined at 823 K for 6 h to remove the template molecules. Metal impregnation and activity evaluation was carried out as per the procedure explained in Example 1 and the same are provided in the Table 5 hereinbelow –
Table 5: Properties of Catalyst 9
Catalyst Reference No.
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Conversion
%
Selectivity
%
Pour point, °C
Catalyst 9
380
0.29
0.5
98.8
5.0
3
[00079] Y zeolite based catalyst exhibited reduced pour point. However, it was still not meeting the required specifications.
16
EXAMPLE 6
[00080] Extrudates of ZSM-5 and catapal alumina were taken in 70:30 ratio. HZSM-5 and Catapal-B were mixed and turned to paste using 10% acetic acid solution in water and molded into cylindrical extrudates by manual press. These extrudates were dried at 373K over night and then calcined at 823K for 6h. This support was then used for metal impregnation and hydroisosmerization reaction activity testing as per the procedure explained in the example 1. Activity results are presented in Table 6 provided hereinbelow –
Table 6: Properties of Catalyst 10
Catalyst Reference No.
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Conversion
%
Selectivity
%
Pour point, °C
Catalyst 10
325
0.3
0.5
55.4
11.7
6
[00081] Catalyst exhibited inferior activity.
EXAMPLE 7
[00082] Refinery spent lobs were used as catalyst for the conversion of hydrotreated vegetable oil to isomerized products. Spent lobs catalyst was subjected to solvent extraction using hexane to remove the trapped hydrocarbons in the catalyst. Hydrocarbon freed sample was subjected to calcination by heating in either air or 2.5% O2 in N2 at the rate of 2oC/min at 540oC for 4Hrs for complete removal of carbon and regenerating the material.
[00083] Discarded refinery LOBS spent catalyst having pore size in the range of 20-150 Å with average pore size of 47 Å. Regenerated LOBS spent catalyst material which has surface area in the range of 200-250 m2/g and pore volume in the range of 0.4 to 0.6 cc/gram was used for treated vegetable oil hydroconversion. Properties for the same are provided hereinbelow in Table 7 –
Table 7: Properties of Catalyst 11
Catalyst Reference No.
Surface Area
(m2/g)
Pore Volume
(ml/g)
Noble Metal (Platinum)
wt%
Pour point, °C
Catalyst 11
225
0.51
0.3
-10
17
EXAMPLE 8
[00084] Continuous fixed bed reaction was carried out in bench scale unit. Catalyst 1 was studied for both hexadecane and hydrotreated vegetable oil (HVO) hydroisomerization activity. Continuous reaction was carried out at 340oC, pressure 20 bar hydrogen, WHSV=1.0h-1 hydrogen flow =25 ml min-1. Product properties are listed in the Table 8, provided hereinbelow -
Table 8: Physical properties of isomerized product of hexadecane and HVO (hydrotreated Vegetable oil)
Feed used
Hexadecane
HVO
Density @ 15º C gm/cm
0.7736
0.7818
KV @ 40ºC mm²/s
2.2295
2.857
Pour Point (ASTM) ºC
-21
-6
ADVANTAGES OF THE INVENTION
[00085] The present disclosure provides a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof.
[00086] The present disclosure provides a method for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof.
[00087] The present disclosure provides a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof that is easy to prepare.
[00088] The present disclosure provides a method of preparation of a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products thereof.
[00089] The present disclosure provides a method of preparation of a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products that is economical.
[00090] The present disclosure provides a method of preparation of a catalyst composition for conversion of vegetable oil derived diesel range hydrocarbons to isomerized products that improves the cold flow properties.

We Claim:
1. A catalyst composition to effect conversion of hydrotreated vegetable oils to isomerized hydrocarbons, the catalyst composition comprising:
(a) an inorganic oxide based porous support in an amount ranging from about 80% to about 99.9% by weight of the composition, wherein said inorganic oxide based porous support comprises alumina in an amount of at least 25% by weight of the inorganic oxide with the remainder being silica; and
(b) at least one noble metal in an amount ranging from about 0.1% to about 10% by weight of the composition.
2. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support is selected from any or a combination of ZSM-5, HY zeolite, SAPO-11 zeolite, HY zeolite and regenerated refinery spent lobs catalyst.
3. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support exhibits pore volume ranging from about 0.25cc/g to about 0.95cc/g, surface area ranging from about 100m2/g to about 700m2/g, unimodal pore size distribution with pores ranging from about 20Å to about 500Å, average pore size ranging from about 20Å to about 100Å.
4. The catalyst composition as claimed in claim 1, wherein the catalyst composition comprises the at least one noble metal in an amount ranging from about 0.1% to about 1% by weight of the composition and wherein the noble metal is Platinum.
5. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support comprises about 20.8% of silica and about 79.2% of alumina, and wherein the inorganic oxide based porous support exhibits unimodel pore size distribution ranging from about 20Å to about 150Å, surface area of about 371 m2/g and pore volume of about 0.80 cc/g.
6. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support comprises about 40.2% of silica and about 59.8% of alumina, and wherein the inorganic oxide based porous support exhibits unimodel pore size distribution ranging from about 20Å to about 250Å, surface area ranging from about 400m2/g to about 500m2/g, bulk density ranging from about 0.80 to about 0.85 g/cc and pore volume of about 0.83cc/g.
19
7. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support is ZSM-5 and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.41cc/g, surface area of about 351m2/g and average pore size of about 48Å.
8. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support is HY zeolite and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.31cc/g, surface area of about 623m2/g and average pore size of about 20Å.
9. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support is SAPO-11 zeolite and amount of the at least one noble metal is about 0.5%, wherein the inorganic oxide based porous support exhibits pore volume of about 0.25cc/g, surface area of about 108m2/g and average pore size of about 91Å.
10. The catalyst composition as claimed in claim 1, wherein the inorganic oxide based porous support is regenerated refinery spent lobs catalyst, wherein the regenerated refinery spent lobs catalyst exhibits surface area ranging from about 200 m2/g to about 250 m2/g and pore volume ranging from about 0.4 cc/gram to about 0.6 cc/gram.
11. The catalyst composition as claimed in claim 10, wherein the regenerated refinery spent lobs catalyst is prepared by subjecting a refinery spent lobs catalyst, with pore size ranging from about 20Å to about 150Å and with average pore size of about 47Å, to solvent extraction to remove any trapped hydrocarbons therefrom, followed by calcinations thereof by heating it in any of (a) air or (b) 2.5% O2 in N2, at a heating rate of 2oC/minutes and at a temperature of about 540oC for 4 hours to effect complete removal of carbon therefrom.
12. A process for conversion of paraffin to isomerized products thereof, the process comprising the step of contacting the catalyst composition, as claimed in claim 1, with paraffin at a pre-determined pressure, and at a pre-determined temperature.
13. The process as claimed in claim 12, wherein the step of contacting the catalyst composition with paraffin is conducted at a hydrogen pressure of about 20bar and at a temperature of about 340°C.
14. A method for preparation of a catalyst composition to effect conversion of hydrotreated vegetable oils to isomerized hydrocarbons, the method comprising the steps of: 20
(a) effecting drying of a pre-determined amount of an inorganic oxide based porous support by heating it in a reactor at about 500°C in air for about 4 hours;
(b) effecting loading of at least one noble metal onto said inorganic oxide based porous support, wherein said loading is effected by any of equilibrium adsorption method and wet impregnation method, and wherein said loading is effected at a room temperature;
(c) effecting drying of said noble metal loaded inorganic oxide based porous support by heating at a temperature ranging from about 110°C to about 120°C and for a time period ranging from about 8 hours to about 16 hours; and
(d) effecting calcinations of the dried noble metal loaded inorganic oxide based porous support at a temperature ranging from about 450°C to 550°C for a time period ranging from about 3 hours to about 4 hours.