TECHNICAL FIELD
[0001] The present disclosure pertains to the technical field of catalyst compositions. In particular, the present disclosure pertains to a method of regeneration of a discarded refinery catalyst. The present disclosure also provides a multifunctional catalyst composition for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process.
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] Nowadays, crude oils available to refineries for up-gradation are becoming heavier. Increasing consumption result in rise in the demand for gasoline, diesel, LPG and other high value products. This trend towards heavy feedstock and demand for high quality products along with strict fuel regulations has raised new challenges for refinery industries. As a result, fluid catalytic cracking (FCC), which is the dark house of refineries for the production of high value gasoline and middle distillates are forced to process vacuum gas oil (VGO) having higher heavier hydrocarbon content.
[0004] In FCC, a fraction of petroleum feed such as vacuum gas oil (VGO) is contacted with particles of hot, reactive catalyst at high temperatures and low pressures of about 1 to 4 atmospheres. The catalyst should be present in adequate quantity, and at an adequate temperature to vaporize the feed, raise the oil feed to a cracking temperature of about 480°C to 590°C and supply the endothermic heat of reaction. The oil and catalyst flow together for hydrocarbon conversion to occur. However, during FCC conversion process of the heavy petroleum feed and middle distillate fractions, by-product coke (carbon) is deposited on the catalyst particles thereby deactivating the catalyst. This type of coke deposited material is often referred to as either "spent catalyst", "discarded refinery catalyst", "equilibrium catalyst", or simply as "ECAT." Spent catalysts or discarded refinery

catalysts that are not capable of suitably performing in another refinery are often disposed in landfills, or incorporated into other industrial processes/products such as cement and road pavement.
[0005] Based on the literature (Fluid Catalytic Cracking Hand Book by Reza Sadeghbeigi published by Gulf publishing Company Houston, Texas 1995 Pages 79-120) the FCC spent catalyst is believed to be a composite material containing alumina, silica and natural clay based material whose catalytic activity had decreased compared to very high activity associated with the fresh catalyst. The loss in activity is mainly due to series of hydrothermal and cracking reactions. Based on the published information, it is believed that the spent catalyst contains about 10-45 wt% of a zeolite mostly with wide pores like "Y "or "X " type and 20-45 wt% of an alumina component, remaining being clay, silica, transition metals and carbon. Typical discarded (or spent) catalyst is a fine powder with an average particle size of about 60-80 microns.
[0006] In past few years, improvement of the performance of spent catalyst has been of great interest. The goal is to improve the activity of the bulk ECAT (spent/discarded) catalyst by chemical treatment. However, such chemical treatments are not routinely practiced for the improvement of spent catalyst in bulk quantity as the cost of performance improvement is even higher than the cost of a fresh catalyst unit. There is, therefore, an unmet long felt need in the art to find a simple and economically feasible process to improve the activity of spent catalyst, and to prepare a multifunctional catalyst additive composition including such spent catalyst that may help in reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process. The present invention satisfies the existing needs, as well as others, and generally overcomes the deficiencies found in the prior arts.
[0007] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition

of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
OBJECTS OF THE INVENTION
[0008] It is an object of the present disclosure to provide a method of
regeneration of a discarded refinery catalyst that may overcome the limitations
associated with the conventional compositions.
[0009] It is an object of the present disclosure to provide a new and improved
multifunctional catalyst composition.
[0010] It is an object of the present disclosure to provide a multifunctional
catalyst composition for reduction of heavier hydrocarbon and enhancement of
gasoline in fluid catalytic cracking process.
[0011] It is another object of the present disclosure to provide a method of
regeneration of a discarded refinery catalyst that is economical.
[0012] It is another object of the present disclosure to provide a method of
regeneration of a discarded refinery catalyst that is easy to perform.
[0013] It is another object of the present disclosure to provide a
multifunctional catalyst composition that is economical, and easy to use.
SUMMARY
[0014] The present disclosure pertains to the technical field of catalyst compositions. In particular, the present disclosure pertains to a method of regeneration of a discarded refinery catalyst. The present disclosure also provides a multifunctional catalyst composition for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process. [0015] An aspect of the present disclosure relates to a method of regeneration of a discarded refinery catalyst, said process comprising the steps of: (a) taking the discarded refinery catalyst, said discarded refinery catalyst being a discarded fluid catalytic cracking (FCC) catalyst; (b) heating the discarded refinery catalyst in presence of at least 1% oxygen concentration at a temperature ranging from 500°C to 600°C for a time period ranging from 2 hours to 6 hours affording

removal of coke; (c) effecting calcinations of the discarded refinery catalyst obtained from step (b) at a temperature ranging from 550°C to 800°C for a time period ranging from 1 hour to 6 hours; (d) effecting chemical treatment of the calcined discarded refinery catalyst obtained from step (c) to obtain a chemically treated discarded refinery catalyst; (e) optionally, filtering, washing and drying the chemically treated discarded refinery catalyst; and (f) effecting a second calcination of the chemically treated discarded refinery catalyst to obtain a regenerated refinery catalyst. In an embodiment, the step of chemical treatment comprises treating the dried discarded refinery catalyst with an acid selected from inorganic acids, organic acids or combination thereof, at a temperature ranging from 70°C to 180°C. In an embodiment, the step of drying of the chemically treated discarded refinery catalyst is effected at a temperature ranging from 90°C to 180°C for a time period of 5 to 18 hours. In an embodiment, the step of second calcination is effected at a temperature ranging from 300°C to 800°C for a time period of 1 to 8 hours. In an embodiment, the discarded refinery catalyst has unimodal pore distribution having pore size in the range of 50°A to 70°A. In an embodiment, the discarded refinery catalyst has average particle size ranging from 60 to 90 microns. In an embodiment, the discarded refinery catalyst has average particle diameter of 15 to 150 microns. In an embodiment, the discarded refinery catalyst has surface area of 100 to 180 m2/g. In an embodiment, the discarded refinery catalyst has matrix surface area of 30 to 70 m2/g. In an embodiment, the discarded refinery catalyst has pore volume of 0.10 to 0.20 cc/g. In an embodiment, the discarded refinery catalyst has bulk density of 0.8 to 0.95 g/cc. In an embodiment, the discarded refinery catalyst has attrition index of 1 to 5 % by weight. In an embodiment, the regenerated refinery catalyst exhibits surface area of 100 to 180 m2/g. In an embodiment, the regenerated refinery catalyst exhibits matrix surface area of 30 to 70 m2/g. In an embodiment, the regenerated refinery catalyst exhibits pore volume of 0.10 to 0.20 cc/g. In an embodiment, the regenerated refinery catalyst exhibits pore size in the range of 50°A to 80°A. [0016] Another aspect of the present disclosure provides a multifunctional catalyst composition for reduction of heavier hydrocarbon and enhancement of

gasoline in fluid catalytic cracking process, wherein said catalyst composition comprises: (i) a regenerated refinery catalyst in an amount ranging from 5% to 40%) by weight of the catalyst composition, said regenerated refinery catalyst comprising chemically treated discarded fluid catalytic cracking (FCC) catalyst comprising: an inorganic oxide in an amount ranging from 5 wt. % to 50 wt. %; an alumino silicate or a zeolite or a combination thereof in an amount ranging from 1 wt. % to 56 wt. %; iron in an amount ranging from 0.1% to 1% by weight; vanadium in an amount ranging from 0.01% to 0.5% by weight; nickel in an amount ranging from 0.05% to 1% by weight; a metal of Group VA in an amount ranging from 0.01% to 1% by weight; a rare earth oxide in an amount ranging from 0.05%) to 4% by weight; and (ii) the remainder being a fluid catalytic cracking (FCC) catalyst. In an embodiment, the inorganic oxide comprises alumina. In an embodiment, the metal of Group VA comprises phosphorus oxide. In an embodiment, the rare earth oxide comprises Cerium oxide and Lanthanum oxide. In an embodiment, the regenerated refinery catalyst exhibits surface area of 100 to 180 m2/g. In an embodiment, the regenerated refinery catalyst exhibits matrix surface area of 30 to 70 m2/g. In an embodiment, the regenerated refinery catalyst exhibits pore volume of 0.10 to 0.20 cc/g. In an embodiment, the regenerated refinery catalyst exhibits pore size in the range of 50°A to 80°A. [0017] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0019] FIG. 1 illustrates an exemplary graph depicting Pore size distribution of discarded refinery catalyst, in accordance with embodiments of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The following is a detailed description of embodiments of the present invention. The embodiments are in such detail as to clearly communicate the invention. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
[0021] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0022] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability.
[0023] Unless the context requires otherwise, throughout the specification which follow, the word "comprise" and variations thereof, such as, "comprises" and "comprising" are to be construed in an open, inclusive sense that is as "including, but not limited to."
[0024] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus,

the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0025] As used in the description herein and throughout the claims that follow, 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.
[0026] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term "about." Accordingly, in some embodiments, the numerical parameters set forth in the written description are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. [0027] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. [0028] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments. [0029] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. "such as") provided

with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention. [0030] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
[0031] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0032] The present disclosure pertains to the technical field of catalyst compositions. In particular, the present disclosure pertains to a method of regeneration of a discarded refinery catalyst. The present disclosure also provides a multifunctional catalyst composition for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process. [0033] An aspect of the present disclosure relates to a method of regeneration of a discarded refinery catalyst, said process comprising the steps of: (a) taking the discarded refinery catalyst, said discarded refinery catalyst being a discarded fluid catalytic cracking (FCC) catalyst; (b) heating the discarded refinery catalyst in presence of at least 1% oxygen concentration at a temperature ranging from 500°C to 600°C for a time period ranging from 2 hours to 6 hours affording removal of coke; (c) effecting calcinations of the discarded refinery catalyst obtained from step (b) at a temperature ranging from 550°C to 800°C for a time period ranging from 1 hour to 6 hours; (d) effecting chemical treatment of the calcined discarded refinery catalyst obtained from step (c) to obtain a chemically

treated discarded refinery catalyst; (e) optionally, filtering, washing and drying the chemically treated discarded refinery catalyst; and (f) effecting a second calcination of the chemically treated discarded refinery catalyst to obtain a regenerated refinery catalyst.
[0034] In an embodiment, the step of chemical treatment comprises treating the dried discarded refinery catalyst with an acid selected from inorganic acids, organic acids or combination thereof, at a temperature ranging from 70°C to 180°C. In an embodiment, inorganic acids, organic acids or combination thereof has a concentration ranging from 0.05 molar to 1.5 molar.
[0035] In an embodiment, the inorganic acids are selected from any or a combination of nitric acid, sulfuric acid, hydrochloric acid, ortho-phosphoric acid, polyphosphoric acid perchloric acid and boric acid. In an embodiment, the organic acids are selected from any or a combination of formic acid, acetic acid, chloroacetic acid, trichloro acetic acid, propionic acid, benzoic acid, methanesulfonic acid, para-toluene sulfonic acid, triflic acid, lactic acid, citric acid, hydroxy acetic acid, succinic acid, maleic acid, oxalic acid and ethylenediamine tetraacetic acid. However, a person skilled in the art would appreciate that any other inorganic acid(s) and/or organic acid(s), as known to or appreciated by a person skilled in the art can also be utilized to serve its intended purpose as laid down in the present disclosure. In an embodiment, pH of the acid ranges from 1.2 to 4.5, preferably, from 1.8 to 4.0.
[0036] In an embodiment, the step of drying of the chemically treated discarded refinery catalyst is effected at a temperature ranging from 90°C to 180°C for a time period of 5 to 18 hours.
[0037] In an embodiment, the step of second calcination is effected at a temperature ranging from 300°C to 800°C for a time period of 1 to 8 hours. [0038] In an embodiment, the discarded refinery catalyst has unimodal pore distribution having pore size in the range of 50°A to 70°A. In an embodiment, the discarded refinery catalyst has average particle size ranging from 60 to 90 microns. In an embodiment, the discarded refinery catalyst has average particle diameter of 15 to 150 microns. In an embodiment, the discarded refinery catalyst

has surface area of 100 to 180 m2/g. In an embodiment, the discarded refinery catalyst has matrix surface area of 30 to 70 m2/g. In an embodiment, the discarded refinery catalyst has pore volume of 0.10 to 0.20 cc/g. In an embodiment, the discarded refinery catalyst has bulk density of 0.8 to 0.95 g/cc. In an embodiment, the discarded refinery catalyst has attrition index of 1 to 5 % by weight. [0039] In an embodiment, the discarded refinery catalyst contains carbon in the range of 0.3% to 1.0% by weight. As noted in the background section, the presence of carbon in the discarded refinery catalyst may result in inactivation of the catalyst (i.e. the reduced or no activity of the catalyst).
[0040] In an embodiment, the discarded refinery catalyst further includes sodium in an amount ranging from 0.01 % to 0.25% by weight; magnesium in an amount ranging from 0.01 to 0.25% by weight; aluminum in an amount ranging from 0.45 to 1.0% by weight; carbon in an amount ranging from 0.30 to 1.0% by weight; phosphorus in an amount ranging from 0.1 to 0.7% by weight. [0041] In an embodiment, the regenerated refinery catalyst exhibits surface area of 100 to 180 m2/g. In an embodiment, the regenerated refinery catalyst exhibits matrix surface area of 30 to 70 m2/g. In an embodiment, the regenerated refinery catalyst exhibits pore volume of 0.10 to 0.20 cc/g. In an embodiment, the regenerated refinery catalyst exhibits pore size in the range of 50°A to 80°A. [0042] Another aspect of the present disclosure provides a multifunctional catalyst composition for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process, wherein said catalyst composition comprises: (i) a regenerated refinery catalyst in an amount ranging from 5% to 40%) by weight of the catalyst composition, said regenerated refinery catalyst comprising chemically treated discarded fluid catalytic cracking (FCC) catalyst comprising: an inorganic oxide in an amount ranging from 5 wt. % to 50 wt. %; an alumino silicate or a zeolite or a combination thereof in an amount ranging from 1 wt. % to 56 wt. %; iron in an amount ranging from 0.1% to 1% by weight; vanadium in an amount ranging from 0.01% to 0.5% by weight; nickel in an amount ranging from 0.05% to 1% by weight; a metal of Group VA in an amount ranging from 0.01% to 1% by weight; a rare earth oxide in an amount ranging

from 0.05% to 4% by weight; and (ii) the remainder being a fluid catalytic cracking (FCC) catalyst.
[0043] In an embodiment, the inorganic oxide comprises alumina. In an embodiment, the metal of Group VA comprises phosphorus oxide. In an embodiment, the rare earth oxide comprises Cerium oxide and Lanthanum oxide. [0044] In an embodiment, the regenerated refinery catalyst exhibits surface area of 100 to 180 m2/g. In an embodiment, the regenerated refinery catalyst exhibits matrix surface area of 30 to 70 m2/g. In an embodiment, the regenerated refinery catalyst exhibits pore volume of 0.10 to 0.20 cc/g. In an embodiment, the regenerated refinery catalyst exhibits pore size in the range of 50°A to 80°A. [0045] CHARACTERSTICS OF DISCARDED REFINERY CATALYST [0046] The discarded refinery catalyst samples were collected from two different FCC units, processing different types of feeds and catalysts. The catalytic activity of these discarded refinery catalyst was very less as compared to fresh catalyst. This loss in activity was mainly due to a series of hydrothermal and cracking reactions. The discarded catalysts were available as a fine powder with an average particle size of about 60 to 90 microns. Characterization data of a discarded refinery catalyst is provided in a Table 1 below and physical properties thereof is provided in the Table 2 below.
Table 1: Characterization of discarded refinery catalyst

Component Amount by wt. of the spent catalyst
Alumina 48.6 %
zeolite 40.5 %
Iron 0.52%
Vanadium 400 ppm
Nickel 0.45 %
Phosphorous Oxide 0.30 %
Cerium oxide and Lanthanum Oxide 1.90%
Iron 0.52%

Table 2: Physical Properties of discarded refinery catalyst

Surface area (m2/g) Attrition index (wt%) Bulk density
(g/cc) Average particle size (u)
Discarded Refinery Catalyst 110 2.5 0.9 75
[0047] PREPARATION OF MULTIFUNCTIONAL CATALYST ADDITIVE COMPOSITION
[0048] Coke deposited on the discarded refinery catalyst was burnt off by
controlled heating in air for about 2 hours at a temperature of about 500°C. Post
coke removal, the discarded refinery catalyst was calcined in air for about 2 hours
at a temperature of about 700°C to oxidize metallic deposits. Representative
samples in examples 1-10 were prepared using this calcined discarded refinery
catalyst.
[0049] Example 1: About 0.1 M solution of nitric acid was added in about 20
grams of calcined discarded refinery catalyst and heated to a temperature of about
100°C for about 2 hours to obtain a chemically treated discarded refinery catalyst.
The chemically treated discarded refinery catalyst was filtered, and the solid
filtered chemically treated discarded refinery catalyst was repeatedly washed with
warm water, and then dried at 110°C for about 16 hours. The dried chemically
treated discarded refinery catalyst was further calcined at 500 °C for about 4 hours
to obtain the regenerated refinery catalyst.
[0050] Example 2: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M sulfuric acid.
[0051] Example 3: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M hydrochloric acid.
[0052] Example 4: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M ortho-phosphoric acid.

[0053] Example 5: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M perchloric acid.
[0054] Example 6: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M acetic acid.
[0055] Example 7: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M lactic acid.
[0056] Example 8: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M methane sulfonic acid.
[0057] Example 9: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M para toluene sulfonic acid.
[0058] Example 10: The regenerated refinery catalyst was prepared by
following the same steps as disclosed in example 1, except the acid used was 0.1
M citric acid.
[0059] Physical properties of the regenerated refinery catalyst is provided in
the Table 3 below and metal content of the regenerated refinery catalyst is
provided in a Table 4 below. Characterization data of the regenerated refinery
catalyst corresponding to Example 3 is provided in a Table 5 below.
Table 3: Physical properties of the regenerated refinery catalyst

Sr. No. Sample Name SA. Matrix area. Micropore area Pore vol.
1 Discarded refinery catalyst 101 46 55 0.110
2 Example-1 107 39 68 0.114

3 Example-2 118 55 63 0.127
4 Example-3 112 41 71 0.119
5 Example-4 105 44 61 0.121
6 Example-5 114 51 63 0.135
7 Example-6 112 43 69 0.124
8 Example-7 107 43 64 0.118
9 Example-8 102 43 59 0.112
10 Example-9 108 41 67 0.125
11 Example-10 110 50 60 0.135
Table 4: Metal content of the regenerated refinery catalyst

Material Fe (wt%) Ni (ppm) V (ppm)
Discarded refinery catalyst 0.5200 4500 400
Example-1 0.3120 4000 343
Example-2 0.3671 3861 357
Example-3 0.3680 3830 368
Table 5: Characterization of the regenerated refinery catalyst

Component Amount by wt. of the spent catalyst
Alumina 47.1 %
zeolite 37.0 %
Iron 0.36 %
Vanadium 368 ppm
Nickel 0.38 %
Phosphorous Oxide 0.28 %
Cerium oxide and Lanthanum Oxide 1.84%
Iron 0.36 %

[0060] ACTIVITY OF MULTIFUNCTIONAL CATALYST
COMPOSITION
[0061] The experimental studies were carried out in a bench scale fixed fluidized bed reactor unit (PC-PLC controlled Advanced Catalytic Evaluation 5 bench scale unit, ACE-R+) licensed by M/s Kayser Technologies, USA. Each experiment was carried out with 6.5 grams of catalyst mixture comprising 10% regenerated catalyst (prepared in example 1 to 10) and 90% fresh FCC equilibrium catalyst. The feed (mixture of VGO and LR/VR in 80:20 proportions) was initially pre-heated to a temperature ranging from 90°C to 140°C. About 1.0
gram of feed was injected at the bottom of the fluidized catalyst bed comprising catalyst mixture. After the cracking reaction, the catalyst composition was thoroughly stripped with N2 to collect all the valuable vapors. Vapors from the reactor were first condensed to collect the liquid product, and the non-condensable gaseous products were collected in a gas collection vessel, and were analyzed
using an on-line Refinery Gas Analyzer (RGA). Liquid product was analyzed off¬line using a Simulated Distillation (SimDist) GC. The coke formed during cracking reaction was burned-off in-situ using zero air and the flue gas is analyzed using FT-IR analyzer. The mass balance sheet provides yields of dry gas (H2-C2), liquefied petroleum gas (LPG, i.e., C3 and C4), gasoline (IBP-216, for us it is
186°C), light cycle oil (LCO, 216-343 °C), heavy cycle oil (HCO, 343-370 °C+), 370+ is CLO and coke. The hydrocarbon conversion was calculated as the summation of dry gas, LPG, gasoline and coke. ACE-MAT activities of the representative are provided herein-below in Table 6, wherein "FCC cat" denotes the fresh FCC equilibrium catalyst and "additive" denotes the regenerated FCC
catalyst of examples 1-10.
Table 6: Activity data of FCC catalyst and the Catalyst mixture

FCC cat FCC cat FCC cat FCC cat FCC cat FCC cat FCC cat FCC cat FCC cat FCC cat
FCC cat. + 10% additive + 10% additive +10% additive +10% additive +10% additive + 10% additive + 10% additive +10% additive +10% additive + 10% additive

(example (example (example (example (example (example (example (example (example (example
1) 2) 3) 4) 5) 6) 7) 8) 9) 10)
Coke 5.96 6.06 6.67 6.22 6.50 6.58 6.04 6.41 6.15 6.73 6.32

DG 1.80 1.78 1.80 1.79 1.82 1.80 1.79 1.83 1.78 1.80 1.84
LPG 17.94 18.18 18.29 18.18 18.16 18.24 17.94 18.23 18.38 18.17 18.55
Gasoline 43.25 40.99 40.92 44.47 42.46 41.05 43.64 39.88 43.45 43.81 43.03
LCO 13.28 14.40 14.26 13.47 12.61 14.65 13.68 14.82 13.94 13.97 13.43
HCO 4.16 4.46 4.34 3.81 4.20 4.40 4.09 4.43 4.06 3.95 3.84
CLO 13.60 14.12 13.74 12.06 14.25 13.29 12.84 14.41 12.24 11.57 12.99
Conversion 68.95 67.02 67.67 70.66 68.94 67.66 69.40 66.35 69.76 70.51 69.74
[0062] It could be noted that the regenerated catalyst is not only cost-effective, but also exhibit activity comparable to a freshly prepared FCC catalyst, as evident from the experimental results provided in Table 6 above. Accordingly, 5 the regenerated catalyst realized in accordance with embodiments of the present disclosure may be used as an additive or even as an independent catalyst (i.e. without mixing with the fresh FCC catalyst) for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process. The presently disclosed method of regenerating a refinery catalyst, regenerated catalyst obtained
thereby and the multifunctional catalyst composition is an economical way for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process.
[0063] While the foregoing description discloses various embodiments of the disclosure, other and further embodiments of the invention may be devised
without departing from the basic scope of the disclosure. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE PRESENT INVENTION
[0064] The present disclosure provides a method of regeneration of a discarded refinery catalyst that may overcome the limitations associated with the conventional compositions.
[0065] The present disclosure provides a new and improved multifunctional catalyst composition.

[0066] The present disclosure provides a multifunctional catalyst composition
for reduction of heavier hydrocarbon and enhancement of gasoline in fluid
catalytic cracking process.
[0067] The present disclosure provides a method of regeneration of a
discarded refinery catalyst that is economical.
[0068] The present disclosure provides a method of regeneration of a
discarded refinery catalyst that is easy to perform.
[0069] The present disclosure provides a multifunctional catalyst composition
that is economical, and easy to use.

WE CLAIM:

A method of regeneration of a discarded refinery catalyst, said process comprising the steps of:
a. taking the discarded refinery catalyst, said discarded refinery
catalyst being a discarded fluid catalytic cracking (FCC) catalyst;
b. heating the discarded refinery catalyst in presence of at least 1%
oxygen concentration at a temperature ranging from 500°C to 600°C for a time period ranging from 2 hours to 6 hours affording
removal of coke;
c. effecting calcinations of the discarded refinery catalyst obtained
from step (b) at a temperature ranging from 550°C to 800°C for a
time period ranging from 1 hour to 6 hours;
d. effecting chemical treatment of the calcined discarded refinery
catalyst obtained from step (c) to obtain a chemically treated discarded refinery catalyst;
e. optionally, filtering, washing and drying the chemically treated
discarded refinery catalyst; and
f effecting a second calcination of the chemically treated discarded refinery catalyst to obtain a regenerated refinery catalyst. The method as claimed in claim 1, wherein said discarded refinery catalyst has unimodal pore distribution having pore size in the range of 50°A to 70°A, average particle size ranging from 60 to 90 microns, average particle diameter of 15 to 150 microns, surface area of 100 to 180 m2/g, matrix surface area of 30 to 70 m2/g, pore volume of 0.10 to 0.20 cc/g, bulk density of 0.8 to 0.95 g/cc and attrition index of 1 to 5 % by weight. The method as claimed in claim 1, wherein the step of chemical treatment comprises treating the dried discarded refinery catalyst with an acid selected from inorganic acids, organic acids or combination thereof, at a temperature ranging from 70°C to 180°C.

4. The method as claimed in claim 1, wherein the step of drying of the chemically treated discarded refinery catalyst is effected at a temperature ranging from 90°C to 180°C for a time period of 5 to 18 hours.
5. The method as claimed in claim 1, wherein the step of second calcination is effected at a temperature ranging from 300°C to 800°C for a time period of 1 to 8 hours.
6. The method as claimed in claim 1, wherein said regenerated refinery catalyst exhibits surface area of 100 to 180 m2/g, matrix surface area of 30 to 70 m2/g, pore volume of 0.10 to 0.20 cc/g and pore size in the range of 50°A to 80°A.
7. A multifunctional catalyst composition for reduction of heavier hydrocarbon and enhancement of gasoline in fluid catalytic cracking process, wherein said catalyst composition comprises:
(i) a regenerated refinery catalyst in an amount ranging from 5% to 40% by weight of the catalyst composition, said regenerated refinery catalyst comprising chemically treated discarded fluid catalytic cracking (FCC) catalyst comprising:
a. an inorganic oxide in an amount ranging from 5 wt. % to 50 wt. %;
b. an alumino silicate or a zeolite or a combination thereof in an
amount ranging from 1 wt. % to 56 wt. %;
c. iron in an amount ranging from 0.1% to 1% by weight;
d. vanadium in an amount ranging from 0.01% to 0.5% by weight;
e. nickel in an amount ranging from 0.05% to 1% by weight;
f a metal of Group VA in an amount ranging from 0.01% to 1% by
weight; g. a rare earth oxide in an amount ranging from 0.05% to 4% by
weight; and (ii) the remainder being a fluid catalytic cracking (FCC) catalyst.
8. The catalyst composition as claimed in claim 7, wherein said inorganic
oxide comprises alumina, said metal of Group VA comprises phosphorus oxide, and said rare earth oxide comprises Cerium oxide and Lanthanum oxide. 9. The catalyst composition as claimed in claim 7, wherein said regenerated refinery catalyst exhibits surface area of 100 to 180 m2/g, matrix surface area of 30 to 70 m2/g, pore volume of 0.10 to 0.20 cc/g and pore size in the range of 50°A to 80°A.