Title of Invention	IMPROVED SORBENT COMPOSITION METHOD FOR THE MANUFACTURE THEREOF AND THE PROCESS FOR REMOVAL OF SULFUR FROM DISTILLATE RANGE FUELS
Abstract	An adsorbent composition for use in the removal of sulfur compounds from hydrocarbon fuels is disclosed. The adsorbent comprises one or more elements selected from group 3d and group VIII of the Periodic Table; a promoter selected from one or more elements of group from 3d, IB, IIA and I A, impregnated or co-precipitated on a support consisting of an element selected from group IIIA or IVA.

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FORM 2 THE PATENTS ACT, 1970 (39 of 1970) & The Patent Rules, 2003 COMPLETE SPECIFICATION (See section 10 and rule 13) TITLE OF THE INVENTION "IMPROVED SORBENT COMPOSITION, METHOD FOR THE MANUFACTURE THEREOF AND THE PROCESS FOR REMOVAL OF SULFUR FROM DISTILLATE RANGE FUELS" We, BHARAT PETROLEUM CORPORATION LTD., of Bharat Bhawan, 4 & 6 Currimbhoy Road, Ballard Estate, Mumbai- 400 001, India. The following specification particularly describes the nature of the invention and the manner in which it is performed: IMPROVED SORBENT COMPOSITION, METHOD FOR THE MANUFACTURE THEREOF AND THE PROCESS FOR REMOVAL OF SULFUR FROM DISTILLATE RANGE FUELS FIELD OF THE INVENTION The present invention relates to a novel adsorbent for use in the removal of sulfur compounds from hydrocarbon fuels. In particular, the present invention relates to a novel adsorbent for use in the removal of sulfur compounds such as organic sulfides, disulfides, mercaptans, thiophenes, benzothiophenes, dibenzothiophenes, and their derivatives from hydrocarbon fuels especially; transportation fuel namely gasoline, kerosene/jet fuel, and diesel and for fuel cell applications. The present invention also relates to a process for the preparation of such novel adsorbents. The present invention also relates to a method for removal of sulfur compounds from hydrocarbon fuels using the adsorbents of the present invention. Background of Invention With increasing stringent regulations in respect of permissible levels of contaminants in transportation fules, refiners are required to produce gasoline having average sulfur level as low as 50 parts per million by weight (ppmw) or even lower, and diesel with average sulfur level of 50 ppmw. Sulfur specifications for gasoline and diesel in most of the countries range from 50 to 500 ppm and are expected to go down to less than 10 ppm in future. Combustion of gasoline and diesel fuels during use in internal combustion engines, in turn, converts the sulfur contaminants into sulfur oxides. The sulfur oxides are environmentally undesirable and also have been found to have a long-term deactivation impact on automotive catalytic converters that are used to remove nitrogen oxide and unburned hydrocarbon contaminants from automotive emissions. In view of this, deep desulfurization of transportation fuels is receiving greater attention than ever before for meeting the stringent regulations and fuel specifications. Ultra low sulfur fuel is also essential for its use in fuel cells. This is because sulfur is a strong poison to reforming as well as fuel cell catalysts. Therefore, the sulfur content in liquid hydrocarbon fuels needs to be reduced to an ultra low level, preferably to less than about 10 ppmw for solid oxide fuel cells and to less than about 1 ppmw for polymer electrolyte membrane fuel cells. 2 Liquid transportation fuels are usually blends of suitable streams from various processing unit in petroleum refining and they contain paraffins, napthenes, aromatics and olefinic compounds and impurities such as compounds of sulfur and nitrogen. It is well known that naphtha from Fluidized Catalytic Cracking (FCC) accounts for majority of the sulfur level and olefins in gasoline pool. Sulfur can be removed from FCC naphtha by the catalytic hydrodesulphurization (HDS) process. This process, however, requires high consumption of hydrogen and significantly reduces fuel octane number due to olefin and aromatics saturation. Because gasoline contains olefins and aromatics, which have high-octane value, selective removal of sulfur without loss of octane is highly desirable. Likewise, desulphurization of diesel to achieve sulfur level of below 50 ppmw demands severe conditions for HDS process operation and high hydrogen consumption. Furthermore, HDS process is not suitable for reducing sulfur content in diesel fuel to below 15 ppmw because the remaining sulfur compounds such as 4,6 dimethyl-dibenzothiophene (4,6-DMDBT) and trimethyl-dibenzothiophene (TMDBT) are refractory and very difficult to remove. Various technologies are currently available or have been proposed which are believed to be capable of reducing sulfur contaminants in gasoline to 30 ppmw or less. According to a recent study conducted by Environmental protection agency (EPA), these available and proposed technologies include hydro treating and adsorption-based processes (see Regulatory Impact Analysis—Control of Air Pollution From New Motor Vehicles: Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements, EPA 420-R-99-023, United States Environmental Protection Agency, December 1999, Chapter IV, pp. IV-42-IV-65). Newly proposed technologies identified in the EPA report include a catalytic distillation technology, called CDTech, which relies upon an HDS catalyst supported in a distillation column to provide reaction of organic sulfur compounds with diene compounds present in FCC naphtha. The resultant thioether reaction product has a higher boiling point and can be removed from the bottom of the distillation column. Similar to conventional hydro treating processes, this process also uses an HDS catalyst. However, hydrogen consumption and olefin saturation are claimed to be lower as compared to conventional hydro treating processes. The operating cost for sulfur removal using the CDTech process is reported to be 25% lower than conventional hydro treating processes for the same degree of sulfur removal. Two emerging adsorption-based desulfurization processes are also discussed in the EPA report. One process, named IRVAD, adsorbs heteroatom-containing hydrocarbon 3 compounds, including sulfur, nitrogen, and oxygen compounds, present in FCC naphtha onto an alumina-based sorbent in liquid phase (see U.S. Pat. No. 5,730,860, issued Mar 24, 1998 to Irvine). The sorbent is fluidized in a tall column and continuously removed and regenerated using hydrogen in a second column. The regenerated catalyst is then recycled back into the reactor. The regeneration of spent sorbent produces a hydrocarbon stream containing about 1 wt % sulfur, which can be treated using conventional processes. While the inventors have claimed an overall cost of sulfur removal as low as 0.77 cents per gallon of gasoline compared to 5 to 8 cents for conventional hydrotreating processes, serious process and system integration issues still remain with this technology, which are hampering its commercial deployment. The other emerging adsorption-based desulfurization technology named as the SZorb process has been developed by the Phillips Petroleum Company. It is understood that this process uses a sorbent comprising one or more metallic promoters, such as a combination of nickel and cobalt, in a zero valence state to selectively remove sulfur compounds from FCC naphtha in the presence of hydrogen. As the sorbent/catalyst becomes saturated with sulfur compounds, it is sent to a regeneration unit where it is treated with an oxygen-containing gas for removal of the sulfur as sulfur dioxide. The oxidized sorbent is further treated with hydrogen in a downstream reducing unit to reduce some of the metal oxide/s present in the sorbent composition to their reduced forms. The reduced sorbent is then fed to the sulfur removal unit, along with hydrogen, for further desulfurization of FCC naphtha. This process is carried out at a temperature between about 250 to about 350 °C and a pressure of 100 to 300 psig. The S-Zorb process uses conventional bubbling-bed fluidized-beds for adsorption and regeneration reactors, which have inherent limitation on throughput of the FCC naphtha feed that can be processed in this system. Phillips claims that this process can remove about 97% of the sulfur from FCC naphtha with a 1 to 1.5 point loss in octane number and with an operating cost of 1.5 to 2 cents per gallon of gasoline. However, the need for a two-step regeneration process, consumption of hydrogen and associated octane number loss, and the use of low throughput bubbling-bed systems are some of the major drawbacks of this technology. On similar lines, US Patent Application No. 20050098478 discloses a process for reducing refractory sulfur level using titanate based sorbents. Various other desulfurization processes are known or have been proposed. For example, U.S. Patent No. 3,063,936, issued on Nov. 13, 1962 to Pearce et al discloses that sulfur reduction can be achieved for straight-run naphtha feedstock from 357 ppmw to 10-26 ppmw levels by 4 hydrotreating at 380 °C using an alumina-supported cobalt molybdate catalyst. According to Pearce et al., a similar degree of desulfurization may be achieved by passing the straight-run naphtha with or without hydrogen, over a contact material comprising zinc oxide, manganese oxide, or iron oxide at 350 to 450 °C. Pearce et al proposed to increase sulfur removal by treating the straight run naphtha feeds in a three-stage process in which the hydrocarbon oil is treated with sulfuric acid in the first step, a hydrotreating process employing an alumina-supported cobalt molybdate catalyst is used in the second step, and an adsorption process, preferably using zinc oxide is used for removal of hydrogen sulfide formed in the hydro treating step as the third step. The process is said to be suitable only for treating feedstock that are substantially free from ethylenically or acetylenically unsaturated compounds. In particular, Pearce et al disclose that the process is not suitable for treating feedstock, such as hydrocarbons obtained as a result of thermal cracking processes that contain substantial amounts of ethylenically or acetylenically unsaturated compounds such as full-range FCC naphtha, which contains about 30% olefins. U.S. Patent No. 5,157,201 discloses that organic sulfur species, primarily comprising organic sulfides, disulfides, and mercaptans, can be adsorbed from olefin streams, without saturating the olefins, by contacting the feed with a metal oxide sorbent at relatively low temperatures (50 to 75 °C), in the absence of hydrogen. The metal oxide sorbent includes metal oxides selected from a group consisting of a mixture of cobalt and molybdenum oxides, a mixture of nickel and molybdenum oxides and nickel oxide supported on an inert support. The adsorbed organic sulfur compounds are removed from the sorbent by purging with an inert gas while heating at a temperature of about 200 °C. for at least about 45 minutes. Although, such low-temperature adsorption processes avoid any olefin saturation, these processes are limited to removal of lighter sulfur compounds such as mercaptans and organic sulfides and disulfides. These processes cannot be used effectively for removal of thiophenes, benzothiophenes, and higher cyclic sulfur compounds, which typically account for greater than 50% of the sulfur in FCC naphtha. Song et.al (Ind. Eng. Chem. Res.; 2005; 44(15); 5740-5749; Energy & Fuels; 2005; 19(3); 1116-1125) have disclosed a sorbent material selected from the group consisting of transition metal chlorides, activated Ni sorbent, metal ion exchanged zeolite, metal ion impregnated zeolite, NiAl-LDHcal, NiZnAl-LDHcal, Ni supported on silica-alumina, regenerated Ni on silica-alumina, sulfided Co—Mo/alumina, and regenerated sulfided metal, and wherein the contacting is performed in a temperature range of about 10 °C. to about 340 °C. However, regeneration of such materials has been a major limitation. 5 US Patent Application No. 20040063576 discloses a method for preparation of Nickel based sorbent material for effectively removing lighter sulfur compounds such as mercaptans and organic sulfides and disulfides from fuel for fuel cell application. However, performance of the sorbent compositions has not been reported for desulfurization of gasoline and diesel fuel. On similar lines, US Patent Application No. 20030113258 illustrates a method for preparing Ni-Cu based sorbent for desulfurization of kerosene having total sulfur level of 150 ppmw for production of hydrogen via steam reforming route. But the performance of such material is not evaluated for desulfurization of heavier petroleum product namely diesel. Furthermore, nickel based sorbents pyrophoric in nature from regeneration point of view. So far, such sorbents are effective for desulfurization of fuels having low total sulfur levels. Yang et.al (J. Am. Chem. Soc; 2004; 126(4); 992-993; Ind. Eng. Chem. Res.; 2001; 40(26); 6236-6239; Ind. Eng. Chem. Res.; 2003; 42(13); 3103-3110) have extensively evaluated the performance of 7i-complexation based sorbents. Such systems are essentially composed of transition ion-exchange zeolites, more specifically, Ni/Cu-exchanged zeolite Y, and have been reported to show high affinity sulfur species present in model feed. However, these systems lack sulfur selectivity in the presence of aromatics, which are major constituents present in gasoline and diesel fuel. Furthermore, the presence of moisture in the feed is reported to affect the performance of these systems. Published US Patent Application No. 20050121365 discloses a process for the desulfurization of a fuel cell feed stream passing the fedd stream over a catalyst adsorbent containing from about 30 percent to about 80 percent nickel or a nickel compound, from about 5 percent to about 45 percent silica as a carrier, from 1 percent to about 10 percent alumina as a propmoter and from about 0.1 to 15 percent magnesia as a promoter. This patent application discloses a very specific embodiment of a sorbent, which it claims to be superior to the generic nickel and alumina based sorbents known but does not disclose any regenerative property of the catalyst. Published US Patent Application No. 20050258077 discloses an adsorbent for removing sulfur compounds from the hydrocarbon streams. The adsorbent composition comprises particles of nickel distributed in a phase including alumina grafted onto a mesoporous silica. This document shows that increased sorption surface area, distributing nickel in a phased a manner on a alumina grafted mesoporous silica suppoprt is rather cumbersome. Furthermore, the regeneration of the used sorbent without the consumption of hydrogen is claimed in the patent application. 6 In summary, currently available and proposed technologies for reducing sulfur content are not only capital intensive, operationally complex, but also typically require significant hydrogen consumption for optimum sorbent performance. This can severely reduce octane number values and/or result in loss in yield for gasoline, and rely on expensive hydrotreating catalysts in whole or in part. Furthermore, regeneration of sorbent materials, which do not demand the presence of hydrogen for their optimum performance, has been a main drawback for process development. A need therefore, exists for a new, cost-effective, sorbent and methods for deep desulfurization of liquid hydrocarbon fuels to meet environmental concerns as well as to produce ultra-low sulfur fuels for fuel cell applications. The present invention now seeks to meet such demands by providing novel sorbent compositions having high sorption area and methods exhibiting high sorption capacity and reversibility for sulfur compounds from hydrocarbon fuels. Objects of the present invention It is therefore, an important object of the present invention to provide an adsorbent composition exhibiting high sorption capacity for sulfur compounds from hydrocarbon fuels. It is yet another object of the present invention to provide a method for the production of a sorbent possessing high sorption capacity for sulfur compounds from hydrocarbon fuels. It is yet another object of the present invention to provide an improved, stable adsorbent in powder, pellet or bead form for selective removal of sulfur compounds from hydrocarbon fuels, which sorbent is a composite comprising of (a) active metal compound (b) a promoter compound and (c) a binder, which is obtainable by methods of co-precipitation, impregnation, hydrothermal aging etc. It is yet another object of the present invention to provide a process for the removal of sulfur from fuels having boiling point in the range of 10 to 360°C by passing through a column containing sulfur selective sorbent. It is yet another object of the present invention to provide a process for the regeneration of sorbent in a single step using hydrogen at elevated temperature or in two steps, first by oxidation followed by reduction for reuse of sorbent. Summary of Invention The above and other objects are achieved by the adsorbent composition of the present invention which comprises from about 20 percent to about 80 percent of metallic nickel or a nickel compound, from about 1 percent to about 20 percent of an aluminum compound, 7 preferably alumina, as a binder, and from about 1 percent to about 10 percent of group IB metallic element as a promoter, wherein all percentages are by weight. The present invention also relates process for reducing the sulfur content in hydrocarbon fuels and liquid hydrocarbon feedstock such as gasoline, kerosene/ aviation fuel and diesel fuel using the sorbent of the present invention Brief description of the accompanying drawings Figure 1 shows the sulfur concentration of the hydrocarbon product from adsorption column of the present invention as a function of volume processed using a preferred adsorbent of the present invention. Figure 2 shows the sulfur concentration of the hydrocarbon product from adsorption column of the present invention as a function of volume processed using another preferred adsorbent of the present invention Detailed description. The composite material, useful in the ultra-deep desulfurization process of the present invention, is preferably prepared by a method comprising (a) co-precipitation of NiO precursor, Ag2O / Li2O / AuO/ SrO/ BaO promoter precursors and alumina binder using sodium carbonate as a precipitating agent at 25 °C (b) aging of the precipitate overnight either in mother liquor providing a material having the surface area 50-200 m /g or under hydrothermal /microwave-hydrothermal conditions at a temperature in the range of 110-150°C providing a material having the surface area 100-300 m2/g. The microwave hydrothermal aging is carried out using MARS-5 unit (CEM Corporation) and hydrothermal aging is performed using high pressure reactor c) washing, drying and finally calcining the material obtained in step-b in air at 400°C. Thus obtained sorbent composition is palletized to form sorbent body in various shapes such as extrudates, granules, and beads etc. using clay, preferably bentonite, and/ or alumina binder. The BET surface area for the prepared compositions was estimated by measuring nitrogen uptake at -196 °C using Autosorb-lC unit (Quantachrome, USA). The performance of prepared sorbent compositions for desulfurization process is evaluated as per the following approach. About 10 g of sorbent produced and calcined, as described above is loaded in the stainless steel column of 1/2" OD and 12" long. The said sorbent, kept at the centre of the column, with the help of inert alumina, to maintain the uniformity, is reduced using H2 with a flow rate in the range of 10-120 cc/min, from 30 °C to 430 °C at the rate of 2 °C per minute, with the holding of 10 Hrs, with intermediate holding of 1 Hr at 200 °C. Then the said sorbent 8 is cooled to reaction temperature and wetted with the solvent, dodecane, to eliminate any trapped gas in the system. The feed having desired sulphur level is passed through the reactor from bottom to top flow at a predetermined processing rate. The samples were collected at different time interval and analyzed for the total and individual sulfur concentration. The total sulfur content is measured using Thermo Euroglass Total Sulfur analyzer (Model: TS 3000) as per ASTM D5453 method. The individual sulfur concentration is measured using GCSCD (Model: GC Clarus 500/Sievers 350) technique. The sulfur concentration as a function of volume processed is monitored. Typically, the fuel which may be treated include LPG, gasoline, kerosene, aviation fuel and diesel fuel having sulfur not more than 2000 ppmw. The invention provides materials and a method for producing ultra low sulfur content transportation fuels for motor vehicles as well as for applications such as fuel cells. The materials and method of the invention may be used at near ambient or elevated temperatures and pressure without directly contacting the hydrogen gas with fuels. Organo-sulfur species such as sulfides, disulfides, mercaptins, thiopenes, benzothiopenes, dibenzothiopenes, substituted thiopenes/ benzothioenes are removed by selective sorption onto a sorbent material, when the procedures and materials of the invention are employed to desulfurize hydrocarbon fuel. When applied to gasoline, sulfur compounds are removed from the gasoline with little or no loss of aromatics, olefinic hydrocarbons or open chain and cyclic paraffinic hydrocarbons. Similarly, the presence of polynuclear aromatics (PNA) in the diesel fuel does not affect the desulfurization performance for the disclosed sorbent. The spent sorbent can be regenerated either by hydrogen in the single step or in two steps via oxidation and reduction step using air and hydrogen, respectively. The present invention provides several advantages. These advantages include but are not limited to the following: • Sulfur removal may be performed at near ambient temperature and pressure, and does not require direct contact of hydrogen, like catalytic hydrodesulfurization (HDS) process • Ultra pure fuels suitable for use in fuel cell systems on-site or on-board may be produced; • Spent sorbent may be easily regenerated. • There is no octane loss when employed to treat gasoline. 9 • The selective sorption of sulfur compounds may be either used as an independent process at non-refinery locations or with the hydrodesulfurization of the concentrated sulfur fraction as an integrated process. The present invention will now be described in detail below by reference to the following detailed description and non-limiting examples. Example 1: An adsorbent is prepared by mixing 2 M aqueous nickel nitrate solution and 0.6 M aqueous aluminum nitrate solution to form mixture-1. 2.4 M aqueous sodium carbonate solution is added to mixture-1 to co-precipitate the carbonate of aluminum, nickel to form the mixture-2. Thus, obtained mixture-2 is aged under hydrothermal conditions at 150°C overnight and subsequently filtered, washed and dried at 110 °C for over night to form the mixture-3. Then the mixture-3 is heated in the presence of air, to 500°C at the heating rate of 2 °C per minute, with intermediate holding for 2 hours at 200°C, and held for 10 hours at 500 °C, to form the mixture-4. Thus obtained product is labeled as sorbent A. Example 2: Another sorbent is prepared by mixing 1.8 M aqueous nickel nitrate solution, 0.025 M aqueous copper nitrate solution and 0.6 M aqueous aluminum nitrate solution and by co-precipitating the precursors using 2.5 M aqueous sodium carbonate solution to form mixture-1. Thus, obtained mixture-1 is filtered, washed and dried at 110 °C for over night to form the mixture-2. Then the mixture-2 is heated in the presence of air, to 500 °C at the heating rate of 2 °C per minute with intermediate holding for 2 hours at 200 °C, and held for 10 hours at 500 °C, to form the mixture-3. The obtained mixture is labeled as sorbent B. Example 3: Another sorbent composition is prepared by mixing 2 M aqueous nickel nitrate solution 0.08 M aqueous lithium nitrate solution and 0.6 M aqueous aluminum nitrate solution to form mixture-1. 2.4 M aqueous sodium carbonate solution is added to mixture-1 to co-precipitate the carbonate of aluminum, lithium and nickel to form the mixture-2. Thus, obtained mixture-2 is aged under microwave-hydrothermal conditions at 150°C for 2-4 hr. and subsequently filtered, washed and dried at 110 °C for over night to form the mixture-3. Then the mixture-3 is heated in the presence of air, to 500°C at the heating rate of 2 °C, with intermediate holding for 2 hours at 200°C, and held for 10 hours at 500 °C to form the mixture-4. Thus obtained product is labeled as sorbent C. 10 Example 4 2 M aqueous nickel nitrate solution 0.07 M aqueous lithium nitrate solution and 0.6 M aqueous aluminum nitrate solution to form mixture-1. 2.4 M aqueous ammonium carbonate solution is added to co-precipitate the carbonate of aluminum, lithium and nickel to form the mixture-2. Thus, obtained mixture-2 is aged under microwave-hydrothermal conditions at 150°C for 2-4 hr. and subsequently filtered, washed and dried at 110 °C for over night to form the mixture-3. Then the mixture-3 is heated in the presence of air, to 500°C at the heating rate of 2 °C, with intermediate holding for 2 hours at 200°C, and held for 10 hours at 500 °C, to form the mixture-4. Thus obtained product is labeled as sorbent D. Similarly, sorbent E and F are prepared using 0.015 M and 0.033 M aqueous silver nitrate solution, respectively and adopting the similar procedure as described above. Like wise, sorbent G is prepared by mixing 0.013 M aqueous gold chloride solution , 2 M aqueous nickel nitrate solution and 0.6 M aqueous aluminum nitrate solution as per the procedure described in example 1. Likewise, for comparison purpose, sorbent H is prepared, as mentioned in patent application no 20040063576 using Nickel nitrate, magnesium nitrate and aluminum nitrate. The performance of the prepared sorbents is evaluated for fuel desulphurization especially for diesel fuel as described in the following examples. Example 5: About 1 g each of the sorbents A, B, C, D, E, F. G, and H, respectively, were loaded in side a glass reactor. Hydrogen gas was passed through the material at the flow rate, not limited to, 120 cc per minute. The material was heat treated in presence of hydrogen to 430 °C at the rate of 2 °C per minute, and held at this temperature for 4 Hrs. Then the said mixture was cooled to reaction temperature, 170 °C under hydrogen flow and transferred to autoclave having diesel with total sulfur level of 540 ppmw and held at 170 °C for 1 hour and the diesel was separated from the sorbent material and analyzed for total sulfur as per ASTM 5453 method. The estimated equilibrium sulfur concentration for various sorbents, using feed diesel having total sulfur of 540 ppmw, are listed in Table 1. Example 6: Sorbents employed in example 5 were regenerated in a single step under the flow of 120 cc/min of hydrogen at 430 °C for 4 hours, and sulfur-uptake capacity measured as per the procedure described in example 5. The uptake capacities for regenerated sorbent are listed in Table-1. 11 Example 7: Sorbents employed in example 5 were regenerated in two steps, first by heating at 430°C under the flow of air followed by heating at 430°C under the flow of hydrogen (120ml/min). Sulfur-uptake capacity of thus regenerated sorbents was measured as per the procedure described in example 5 and listed in Table-1. Table 1: Sulfur uptake capacities for various sorbents for Feed having total sulfur level of 540 ppmw Sorbent Fresh material Single step regeneration Two step regenration Eq.Conc,ppmw Capacity, mg/g Eq. Conc, ppmw Capacity, mg/g Eq. Conc, ppmw Capacity, mg/g A 260 2.1 345 1.5 290 1.9 B 163 2.8 318 1.7 210 2.5 C 116 3.2 326 1.6 294 1.8 D 97 3.3 173 2.8 120 3.2 E 142 3.0 201 2.5 148 2.9 F 141 3.0 249 2.2 157 2.9 H 146 3.0 280 2.0 300 1.8 Example 8: About 10 g of sorbent C produced and calcined, as described in example 3 is loaded in the stainless steel column of ½” OD and 12" long. The said sorbent, kept at the centre of the column, with the help of inert alumina, to maintain the uniformity, is reduced using H2 with a flow rate of 120 cc/min, from 30 °C to 430 °C at the rate of 2 °C per minute. Then the said sorbent is cooled to reaction temperature and wetted with the solvent, dodecane, to eliminate any trapped gas in the system. The feed having desired sulphur level is passed through the reactor from bottom to top flow at a predetermined processing rate. The samples were collected at different time interval and analyzed for the total and individual sulfur concentration. The total sulfur content is measured using Thermo Euroglass Total Sulfur analyzer (Model: TS 3000) as per ASTM D5453 method. The desulfurization treatment for the feed having total sulphur of 540 ppmw is carried out as per the procedure described above. The feed is passed through the reactor at 170 °C with a processing rate, WHSV, of 1 Hr_1. The samples were collected at different time interval and analyzed for the total sulfur concentration. The total sulfur content is measured as per the ASTM method D5453. The sulfur concentration as a function of volume processed is depicted in Fig. 1 which demonstrates the elution of the sulfur concentration in the product as a function of volume of 12 feed processed. The eluted cumulative sulfur concentration is found to be less than 10 ppmw for the processed feed of 12 cc/g of sorbent C. Example 9: The desulfurization treatment using sorbent D as per the procedure described in example 8 for feed containing total sulfur level of about 500 ppmw, in terms of heavy refractory sulfur species, is performed. The feed is passed thro' the reactor with a processing rate, WHSV, of 2 Hr-1. The samples were collected at different time interval and analyzed for the total and individual sulfur concentration as mentioned above. Like example 8, the profile for sulfur concentration as a function of feed processed volume is shown in Figure 2. The eluted cumulative sulfur concentration is found to be less than 20 ppmw for the processed feed of 6 cc/g under the experimental conditions 13 We claim: 1. An adsorbent composition for use in the removal of sulfur compounds from hydrocarbon fuels which comprises one or more elements selected from group 3d and group VIII of the Periodic Table; a promoter selected from one or more elements of group from 3d, IB, IIA and I A, impregnated or co-precipitated on a support consisting of an element selected from group IIIA or IVA. 2. An adsorbent as claimed in claim 1 wherein nickel and one or more of silver, gold, lithium, barium and strontium precursors are impregnated or co-precipitated over an alumina support.. 3. An adsorbent as claimed in claim 1 or 2 having a surface area of 100-300 m7g, preferably, 150-200 m2/g. 4. An adsorbent as claimed in any preceding claim wherein said promoter comprises of one or more of silver and gold in the range of 0.1 wt % to 4 wt %, preferably, in the range of 1.5 wt% to 2.5 wt%. 5. An adsorbent as claimed in any preceding claim wherein said promoter comprises lithium in the range of 0.1 wt% to 0.5 wt%. 6. An adsorbent as claimed in any preceding claim wherein said promoter comprises said silver, lithium or gold reduced from their corresponding oxide. 7. An adsorbent as claimed in any preceding claim wherein said support is alumina. 8. An adsorbent as claimed in any preceding claim in the form of powder and or pellet/ bead and/or extrudates in the size range of 0.2 to 5 mm. 9. A method of preparation for the adsorbent as claimed in any preceding claim which comprises impregnation and/or co-precipitation of the nickel, and one or more of silver, gold, lithium, barium and strontium precursors over an alumina support. 14 10. A method as claimed in claim 9, wherein the said impregnation is carried out by hydrothermal or microwave hydrothermal aging of nickel, and one or more of silver, gold, lithium, barium and strontium precursors over an alumina support 11. A method as claimed in claim 9 or 10 wherein said adsorbent is formed using precursors preferably of hydroxides and carbonates form and more preferably of carbonate form 12. A process for the removal of sulfur compounds from hydrocarbon fuels which comprising: (i) providing a sorbent comprising one or more elements selected from group 3d and group VIII of the Periodic Table; a promoter selected from one or more elements of group from 3d, IB, IIA and I A, impregnated or co-precipitated on a support consisting of an element selected from group IIIA or IV A; (ii) activating said adsorbent with hydrogen; (iii) passing a hydrocarbon feed containing total sulfur not more than 2000 ppmw; and (i) regenerating the adsorbent for reuse. 13. A process as claimed in claim 12, wherein the activation of the adsorbent is carried out at a temperature in the range of 350 to 500°C. 14. A process as claimed in claim 12 or 13 wherein said hydrocarbon feed has sulfur content not more than 2000ppmw and in the boiling point range of 10 - 360°C. 15. A process as claimed in any one of claims 12 to 14 wherein the group 3d and/or group VIII element is preferably nickel and/or palladium, and/or platinum more preferably nickel. 16. A process in any one of claims 12 to 15 wherein said nickel is reduced form of nickel oxide 17. A process as claimed in claim 16 wherein said nickel oxide is obtained through calcination of nickel oxide precursor, preferably nickel carbonate / nickel hydroxide 15 18. A process as claimed in any one of claims 12 to 17 wherein said nickel is in the range of 60wt.% to 85wt.% 19. A process as claimed in any one of claims 12 to 18 wherein said nickel and one or more of silver, gold, lithium, barium and strontium precursors are impregnated or co-precipitated over an alumina support.. 20. A process as claimed in any one of claims 12 to 19 wherin said adsorbent has a surface area of 100-300 m2/g, preferably, 150-200 m2/g. 21. A process as claimed in any one of claims 12 to 20 wherein said promoter comprises of one or more of silver and gold in the range of 0.1 wt % to 4 wt %, preferably, in the range of 1.5 wt% to 2.5 wt%. 22. A process as claimed in any one of claims 12 to 21 wherein said promoter comprises lithium in the range of 0.1 wt% to 0.5 wt%. 23. A process as claimed in any one of claims 12 to 22 wherein said promoter comprises said silver, lithium or gold reduced from their corresponding oxides. 24. A process as claimed in any one of claims 12 to 23 wherein said support is alumina. 25. A process as claimed in any one of claims 12 to 24 wherein said adsorbent is in the form of powder and or pellet/ bead and/or extrudates in the size range of 0.2 to 5 mm. 26. A process as claimed in any one of claims 12 to 25 wherein the process is carried out with or without directly contacting hydrogen. 27. A process as claimed in any one of claims 12 to 26 wherein the process is carried out at a temperature in the range of 100 ° C to 400 ° C, preferably 200 ° C. 28. A process as claimed in any one of claims 12 to 27 wherein the process is carried out at a pressure in the range of from 1 atm to 15 atm, preferably, 2 atm. 16 29. A process as claimed in any one of claims 12 to 28 wherein the process is earned out in the weight hourly space velocity range of 0.5 Hr –1 to 5 Hr_1, preferably 2 Hr-1 30. A process as claimed in any one of claims 12 to 29, wherein the process is carried out with hydrocarbon stream containing oxygenates. 31. A process as claimed in any one of claims 12 to 30 wherein the process is carried out, with or without directly contacting with hydrogen, in the temperature range of 30 °C to 400 °C preferably 50°C. 32. A process as claimed in any one of claims 12 to 31 wherein the said adsorbent is regenerated through directly and/or indirectly contacting solvent and/or hydrogen and/ or air and/or nitrogen. 33. A process as claimed in claim 32, wherein the said adsorbent is preferably regenerated by directly contacting with hydrogen in the temperature range of 350-550 °C and more preferably at 400 °C. 34. A process as claimed in claim 32 or 33, wherein the said adsorbent is regenerated for duration of 0.5-10 hours, preferably up to 2 h. 35. A process as claimed in any one of claims 12 to 34 wherein the said adsorbent is preferably regenerated using hydrogen flow rate ranging from 2-20 cc/g and more preferably in the range of 4-6 cc/g. 36. A process as claimed in claim 32, wherein the said adsorbent is preferably regenerated by solvent stripping by employing polar solvents such methanol followed by direct activation with hydrogen in the temperature range of 150-550 °C and more preferably in the range of 200-350 °C. Dated this 5th day of June 2006 H. SUBRAMANIAM Of Subramaniam Nataraj & Associates Attorneys for the Applicants Abstract An adsorbent composition for use in the removal of sulfur compounds from hydrocarbon fuels is disclosed. The adsorbent comprises one or more elements selected from group 3d and group VIII of the Periodic Table; a promoter selected from one or more elements of group from 3d, IB, IIA and I A, impregnated or co-precipitated on a support consisting of an element selected from group IIIA or IVA. 18

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912-MUM-2006-DESCRIPTION(GRANTED)-(29-8-2013).pdf

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912-mum-2006-form 1(21-7-2006).pdf

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912-MUM-2006-FORM 18(11-8-2009).pdf

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912-MUM-2006-FORM 26(26-12-2012).pdf

912-MUM-2006-FORM 26(31-7-2013).pdf

912-MUM-2006-FORM 3(19-7-2013).pdf

912-MUM-2006-FORM 3(26-12-2012).pdf

912-MUM-2006-FORM PCT-IPEA-409(15-2-2012).pdf

912-MUM-2006-FORM PCT-ISA-237(15-2-2012).pdf

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912-mum-2006-form-2.pdf

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912-MUM-2006-REPLY TO HEARING(12-8-2013).pdf

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912-MUM-2006-SPECIFICATION(AMENDED)-(26-12-2012).pdf