Title of Invention	A SUPER ACID CATALYST COMPOSITION AND METHOD FOR THE PREPERATION THEREOF.
Abstract	Catalyst comprising sulfated metal oxide synthesized via solution combustion synthes. A mesoporous superacidic is having surface area in the range of 1 to 1000 m2/g, pore diameter in the range of 2 to 25 run and pore volume in the range of 0.01 to 3 cm3/g for use in acid catalyzed reactions which occur in the mesoporous range of the catalysts. The catalyst of the said invention comprises atleast 0.1 to 20 mass percent of sulfur in the form of sulfate group. Application side of the said catalyst has shown remarkable activity in the reaction of Pechmann condensation and Friedal Craft"s alkylation.

Title of Invention

A SUPER ACID CATALYST COMPOSITION AND METHOD FOR THE PREPERATION THEREOF.

Abstract

Catalyst comprising sulfated metal oxide synthesized via solution combustion synthes. A mesoporous superacidic is having surface area in the range of 1 to 1000 m2/g, pore diameter in the range of 2 to 25 run and pore volume in the range of 0.01 to 3 cm3/g for use in acid catalyzed reactions which occur in the mesoporous range of the catalysts. The catalyst of the said invention comprises atleast 0.1 to 20 mass percent of sulfur in the form of sulfate group. Application side of the said catalyst has shown remarkable activity in the reaction of Pechmann condensation and Friedal Craft"s alkylation.

Full Text	FORM2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See section 10 and rule 13) 1. TITLE OF THE INVENTION "COMBUSTION SYNTHESISED ZIRCONIA AS MATERIAL AND CATALYST" 2. APPLICANT NAME : YADAV GANAPATI DADASAHEB (Last Name/Surname) (First Name) (Father's Name/Middle Name) NATIONALITY: INDIAN ADDRESS : CHEMICAL ENGINEERING DEPARTMENT, INSTITUTE OF CHEMICAL TECHNOLOGY (DEEMED UNIVERSITY), NATHALAL PARIKH MARG, MATUNGA (EAST) MUMBAI 400 019 INDIA The following specification particularly describes the invention and the manner in which is to be performed. FIELD OF THE INVENTION The present invention relates to a new heterogeneous super acidic catalyst for use in various acid catalyzed reactions of organic compounds for expected shape selectivity, in the mesoporous range and its method of manufacture. The catalyst of the present investigation's in the field of solution combustion synthesis of metal oxides and particularly relates to preparation of superacidic sulphated metal oxides via solution combustion synthesis route. BACKGROUND OF INVENTION The use of highly acidic catalysts is very rampant in chemical and refinery industries, and those technologies employing highly corrosive, hazardous and polluting liquid acids are being replaced with super acidic catalysts. Of late, a number of organic syntheses have been conducted with solid acids leading to better chemo-, regio- and stereo- selectivity. In industrial catalytic reaction, it is highly desirable to have high density of surface exposed to active sites in reactor volume. New technologies and recipes are evolving everyday which synthesize catalysts with increased number of active sites. Preparation, characterization and catalytic investigations of sulfated metal oxides elicited an almost unique interest in the past decade. The beginning of this extraordinary effort was in 1979, when Arata et al. reported in Journal of Chemical Society Chemical Communication (1979), 1148 that zirconia upon proper treatment with, sulfuric acid or ammonium sulfate, exhibits acidity 104 times stronger than that of 100% sulfuric acid United States patent 3,032,599 is one of the first patents to disclose synthesis of sulfated zirconia catalyst and its application in isomerization and alkylation reaction. In this method zirconia gel is prepared by precipitation of zirconyl salt in water by addition of base. The obtained zirconia gel is then sulfated using ammonium sulfate and activated by calcination at 500 °C. The catalyst showed acid catalytic properties but not satisfactory due to low sulfur content. United States patent 4,873,017 discloses the method of preparation of anion bound metal oxide catalyst in which the anion can be S04, BF3, CO3, BO3, HPO4, M0O4, B4O7 or PF6 and metal oxide can be zirconium oxide, nickel oxide, aluminium oxide, tin oxide, magnesium oxide, rubidium oxide, titanium oxide or thorium oxide. In the method to prepare sulfate modified zirconium oxide, zirconium hydroxide is prepared by hydrolysis of zirconium oxychloride with ammonium hydroxide. The hydroxide is treated with sulphuric acid followed by calcination at 600°C. The catalyst showed 2-3 % w/w sulfur and excellent activity towards alkoxylation of active hydrogen compounds like primary and secondary alcohols. Japanese patent 56033037 discloses a method for synthesis of sulfated metal oxide catalyst of high acidity used for isomerization and alkylation. In this method hydroxide or oxide of iron is treated with a solution containing sulfuric acid group, such as sulfuric acid, ammonium sulfate etc. by scattering or immersion, then it is dried and calcined so as to activate it thereby manufacturing a catalyst which is used for isomerization or alkylation in petroleum refining or petro chemistry. The catalyst hereby manufactured allows performing isomerization and alkylation without causing corrosion of the apparatus. United States patent 5,182,247 discloses a method of preparation of sulfated metal oxide in which the metal oxide was impregnated with a solution of concentrated sulfuric acid dissolved in deionized water. The impregnated catalyst was dried overnight and calcinated at 620°C. Analysis of this material showed it to contain 3.29 % w/w sulfur. United States patent 5,786,294 discloses a method to produce a sulfated zirconia catalyst in which a mixture of hexadecane amine and DI water is heated and added to another mixture of zirconium isopropoxide, acetyl acetone and anhydrous ethanol. The above mixture is stirred vigorously and precipitate is filtered out. The separated solid is extracted with ethanol and - - soaked into sulfuric acid. The solids are dried and calcinated to get an active catalyst. The catalyst showed pore diameter in the range of 2.5 to 4.7 nm and tetragonal phase with BET surface area in the range of50m2/gto 150m2/g. United States patent 5,036,035 discloses a method to produce a wide variety of supported sulfated metal oxide catalyst in which at least one member is selected from group VIII metals on a support consisting of hydroxides and oxides of group IV metals and group III metals and mixture thereof. In this method zirconium hydroxide is prepared from precipitation of zirconium oxychloride with aqueous ammonia followed by drying. This support is impregnated with aqueous solutions of chloroplatinic acid, drying and treatment with sulphuric acid. The material is calcinated at 650°C to get an active catalyst. United States patent 5,719,097 discloses a method to produce a catalyst comprising a hydrogenation/dehydrogenation component, such as a noble metal and an acidic solid component comprising a group IVB metal. In this method zirconium hydroxide is prepared from precipitation of zirconium oxychloride with aqueous ammonia followed by drying. The dried hydroxide was impregnated via incipient wetness method with an aqueous solution containing ammonium metatungstate. The resulting material is dried and calcinated to get an active catalyst. United States patent 6,448,198 Bl discloses a method of preparation of sulfated metal oxide in which alumina support is impregnated with a solution of zirconium oxychloride, ammonium chloride and water. The impregnated mixture is dried and calcinated prior to sulfation with sulphuric acid. The sulfated mass is dried and platinum is deposited using chloroplatinis acid solution. Drying and calcination of the material resulted into final catalyst. The previous art of zirconia and related sulfated metal oxide catalysts have associated with them a number of deficiencies resulting from their microporous nature and lower sulfur content. The pore structure can be determinative of catalyst stability and/or activity. Various attempts have been made to synthesize sulfated zirconia with pores in mesoporous range. Use of charged template is reported in Catalysis Letters (1996), 38, 219. But removal of template by calcination -caused this material to collapse. Use. of cationie surfactant was reported in Journal of Material Chemistry (1996), 6, 89. This material showed mesoporosity but with very wide pore size distribution (width at half height mesoporous material, the neutral templating method, which uses long-chain primary alkyl amines as template. All these methods have used an approach in which the:metal hydroxide is prepared from metal salt by hydrolysis with a base followed by acid treatment and calcination. Use of combustion synthesized metal oxides in preparation of sulfated metal oxides has not been reported yet. The method of combustion synthesis was first reported in Combustion and Flame (1969), 13(2), 143-56. The combustion synthesis method explores an exothermic, generally very fast and self-sustaining chemical reaction between the desired metal salts and a suitable organic fuel, which is ignited at a temperature much lower than the actual phase formation temperature. Its key feature is that the heat required to drive the chemical reaction and accomplish the compound synthesis is supplied by the reaction itself and not by an external source. United States patent 6,761,866 Bl discloses a method of combustion synthesis for the synthesis of nanoparticles of a phase pure ceramic oxide of a single component system which includes preparing a solution containing the metal ion by dissolving a salt of the metal ion in an organic solvent or in water. A complexing agent is added in this solution keeping the ratio of charges of the metal ion as unity. Addition of nitric acid and ammonia or nitric acid and ammonium hydroxide is done in order to adjust nitrate and ammonia content of solution followed by heating at 250 °C to 300 °C to produce foam which subsequently ignites to produce combustion product comprising nanoparticles. United States patent 5,114,702 discloses the method of producing mixed metal oxide using combustion synthesis method in which metal nitrates and organic fuel are dissolved in minimum quantity of deionized water. The mixture is heated on a hot plate to form a concentrated combustible solution which is further heated in a small quantity to approximately 200 °C. The product was formed on. auto ignition which was calcined to remove volatile residuals. US patent application US 2005/0095194 A1 discloses a method of producing zinc oxide in which zinc nitrate and glycine were mixed in predetermined amount in deionized water o form a homogenous solution with constant stirring. The mixture was heated on a hot plate to transform it into combustible gel. The gel was heated up to its auto ignition temperature to form zinc oxide nanoparticles. Use of carbohydrazide as a fuel and nitric acid as an additive has also been reported. All these methods have reported synthesis of metal oxides using combustion synthesis method involving an exothermic reaction between metal salt and fuel. But use of combustion synthesized metal oxide is synthesis of sulfated metal oxide catalyst and their use as catalytic material has not been reported yet. OBJECTIVE OF INVENTION It is the objective of present invention to provide a heterogeneous solid acid catalyst possessing high sulfur content, high acidity and mesoporosity with high selectivity towards bulky molecules. Yet another objective of the present invention is directed to providing for a superacidic metal oxide catalyst via combustion synthesis route to achieve desired mesoporosity and narrow pore size distribution. Another objective of present invention is to design a superacidic catalyst with retention of tetragonal phase, Another objective of the present invention is to design catalyst having sulfur content in the range of0.5to20%w/w. Another objective of the present invention is to design catalyst having specific surface area in the - -range 1 m2/g..to-1000 m2/g, pore diameter in the range of 2 to 25 nm and pore volume in the-range of 0.01 to 3 cmVg. SUMMARY OF THE INVENTION The present invention provides a simple method of solution combustion synthesis for preparation of sulfated metal oxide catalysts in which the metal can be Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof. The said solid acid catalyst has metal oxide as a basic composition and at least 0.5 to 20 % w/w of sulphur in the form of sulfate wherein catalyst specific surface area is in the range 1 m2/g to 1000 m2/g. BRIEF DESCRIPTION OF DRAWINGS Drawing I: SEM (Scanning Electron Microscope) images of fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 2: NH3-TPD (Temperature Program Desorption) of fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 3: FT-IR (Fourier transform Infra red) graph for fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 4: Pore size distribution of fuel lean zirconia, fuel rich zirconia, fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 5: XRD (X-Ray Diffraction) Analysis of zirconia, fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) DETAILED DESCRIPTION OF INVENTION International Union of Pure and Applied Chemistry (IUPAC) define pores having width in the range of 2 nm to 50 nm as mesopores and those with width less than 2 nm are micropores. For catalytic processes involving bulky reactants, pore dimensions of greater than 2 nm are required for better shape selectivity. The pore structure of sulfate modified metal oxides is largely controlled by the preparation method and calcination temperature. The conventional precipitation - method results into microporous material which is mere suitable for reactions of small molecules in the vapor phase. To form a catalyst that has shape selectivity for larger molecules, mesoporous material with narrow pore-size distributions needs to be created. The amount of sulphur loading decides the acidity and activity in sulfated metal oxide catalyst. In sulfated zirconia catalyst the retention of tetragonal phase is necessary for better activity of catalyst. It is a challenge to achieve higher sulphur loading with retention of tetragonal phase as sulphur loading above 4 % results into generation of secondary monoclinic phase along with major tetragonal phase. Very high sulfur loading results in formation of metal sulfates instead of sulfated metal oxide. All previous literature suggests that S-Z1O2 has been prepared so far with a maximum 9% w/w of sulfur with preservation of the tetragonal phase of zirconia and above this value the tetragonal phase is strongly affected. In recent years, combustion synthesis has emerged as a powerful alternative for material synthesis. This method is highly reproducible, less time consuming and does not involve multi step synthesis. This method produces fine nano scale metal oxides with high surface area and synthesis method explores an exothermic, generally very fast and self-sustaining chemical reaction between the desired metal salts and a suitable organic fuel, which is ignited at a temperature much lower than the actual phase formation temperature. Here the metal salts can be nitrates, acetates etc. whereas the frequently used fuels are glycine, urea and carbohydrazide. Its key feature is that the heat required to drive the chemical reaction and accomplish the compound synthesis is supplied by the reaction itself and not by any external source. The fuel to oxidizer ratio governs the surface properties of combustion synthesized metal oxides. When the fuel and oxidizer are in stoichiometric amount, neither atmospheric oxygen is required for combustion nor it is evolved in the combustion. When the fuel to oxidizer ratio is lower than the stoichiometric composition, then the precursor mixture is called fuel lean composition and when the fuel to oxidizer ratio is higher than stoichiometric ratio it is called fuel rich composition. At fuel lean composition, the adiabatic flame temperature is low due to comparatively less-fuel--which results into comparatively less sintering of material which enhances the surface area. On the other hand the amount of gasses evolved is less compared to fuel rich composition which results into lowering of surface area. At fuel rich composition though the amount of gas evolution is substantially higher, higher flame temperature results into sintering of material. All these factors make it difficult to predict the surface area variation with fuel to oxidizer ratio. It is observed that the surface area is higher in fuel lean and fuel rich conditions compared to stoichiometric conditions. Hence for catalytic applications, it is always advisable to operate in fuel lean or fuel rich composition. The heterogeneous catalyst of the present invention is calcinated catalyst composition which comprising at least 20-70 mass percent metal, 25-60 mass percent of oxygen and 0.5 to 20 mass percent of sulphur prepared via combustion synthesis method. Thus resultant calcinated catalyst composition has surface area in the range of 1 to 1000 m2/g, pore diameter in the range of 2 to 25 nm and pore volume in the range of 0.01 to 3 cm3/g. One of embodiments of the invention is that in the calcinated catalyst composition, metal ion is Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof. One of embodiments of the invention is that in the calcinated catalyst composition, metal ion is preferably Zr, Al, Ti, Ce and/or mixture thereof. One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, metal ion precursor used are in form of nitrate, sulphate, oxynitrate, isopropoxide, formate, carbonate, bicarbonate, acetate, oxyhalide, hydroxide and/or mixture thereof. One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, the metal ion precursor used is preferably nitrate and oxynitrate. One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, fuel used is urea, citric acid, carbohydrazide, oxalyldihydrazide, malonic acid hydrazide, tetraformal trisazine, methyl -acetate, ammonium citrate, ammonium nitrate, ammonium tartarate, amino acids and/or mixture thereof. One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, fuel used is preferably glycine, citric acid urea, carbohydrazide and/or mixture thereof. General method for production of calcinated catalyst composition comprises a. forming a substantially homogeneous, aqueous precursor mixture containing atleast one substantially water soluble metal salt precursor and a substantially water soluble combustible organic fuel b. heating the said aqueous precursor mixture to form a substantially homogeneous combustible gel c. auto igniting and combusting the gel to produce the metal oxide d. sulfation of the metal oxide with atleast one sulfating agent to deposit sufficient sulphate species e. calcinating the acid treated metal oxide The activity of the catalyst is tested for Pechmann condensation reaction between resorcinol and ethyl acetoacetate and also for Friedel Craft's benzylation of toluene. In further accord with the present invention, the catalyst comprises of sulfate modified oxides of Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof. This heterogeneous catalyst is separated from the reaction mixture by filtration. EXAMPLE 1: FUEL LEAN SULFATED ZIRCONIA CATALYST PREPARATION In fuel lean sulfated zirconia catalyst (FLSZ), the mole ratio of zirconium oxynitrate hexahydrate [ZrO(N03)2.6H20] and glycine is less than the stoichiometric mole ratio. In synthesis of this catalyst, the initial mixture contains glycine and zirconium oxynitrate hexahydrate in 1:2 molar ratio. In the method to synthesize around 3 g of fuel lean sulfated zirconia catalyst, 1 g of glycine and 9 g of zirconium oxynitrate hexahydrate are diluted in 20 ml of Dl water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline zirconium dioxide powder. This material is immersed in 15 cm3/g of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating is started to evaporate the solvent. This material is kept in oven at 120 °C for 24 h and calcined at 650 °C for 3 h to get around 3 g of the active catalyst FLSZ. EXAMPLE 2: FUEL RICH SULFATED ZIRCONIA CATALYST PREPARATION In fuel rich sulfated zirconia catalyst (FRSZ), the mole ratio of zirconium oxynitrate hexahydrate [ZrO(N03)2.6H20] and glycine is higher than the stoichiometric mole ratio. In synthesis of this catalyst, the initial mixture contains glycine and zirconium oxynitrate hexahydrate in 2:1 molar ratio. In the method to synthesize around 3 g of fuel lean sulfated zirconia catalyst (glycine to nitrate mole ratio = 2), 4 g of glycine and 9 g of zirconium oxynitrate hexahydrate are diluted in 25 ml of DI water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline zirconium dioxide powder. The oxide with fuel rich initial composition consist considerable amount of residual carbon. To remove this unwanted carbon, the zirconium dioxide powder is calcined at 550 °C for 4 h prior to acid treatment. The material is then immersed in 15 cmVg of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating started to evaporate the solvent. This material is kept in the oven at 120 °C for 24h and calcined at 650 °C for 3 h to get around 3 g of the active catalyst FRSZ. FLSZ and FRSZ are characterized by following techniques Drawing 1: SEM (Scanning Electron Microscope) images of fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 2: NH3-TPD (Temperature Program Desorption) of fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 3: FT-IR graph for fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 4: Pore size distribution of fuel lean zirconia, fuel rich zirconia, fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) Drawing 5: XRD Analysis of zirconia, fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) EDX results are as follows Table 1 Element FLSZ(%) FRSZ(%) O 38.8 38.6 S 15.14 15.1 Zr 46.05 46.3 Both the catalysts showed substantially high sulfur content (S > 15 % w/w) ASAP results are as follows Table 2 Surface area (m2/g) Pore Size A° Pore Volume Cm3/g FLSZ 53.26 98.48 0.131 FRSZ 21.63 91.43 0.051 Both catalysts showed pore size in the mesoporous range. EXAMPLE 3 SULFATED TITANIA CATALYST PREPARATION In the method to synthesize around 3 g of sulfated titania (SCVVTiOi) catalyst, 3.96 g of glycine and 9 g of titanyl nitrate [TiO(NO3)2] are diuted in 25 ml of DI water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline titanium dioxide powder. The material is then immersed in. 15 cm3/g of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating started to evaporate die solvent. This material is kept in the oven at 120 °C for 24h and calcined at 550 °C for 3 h to get around 3 g of the active catalyst sulfated titania. EXAMPLE 4 SULFATED CERIA ZIRCONIA CATALYST PREPARATION In the method to synthesize around 3 g of sulfated ceria zirconia (SO^VCeo.sZro.sOi) catalyst, 3.24 g of carbohydrazide, 5 g of Ce(N03)3.6H20 and 3.9 g of Zr(N03)2.6H20 diuted in 25 ml of DI water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline Ceo.5Zro.5O2 powder. The material is then immersed in 15 cm3/g of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating started to evaporate the solvent. This material is kept in the oven at 120 °C for 24 h and calcined at 650 °C for 3 h to get around 3 g of the active catalyst SO427Ce0.5Zr0.5O2. EXAMPLE 5-8 A series of reactions for synthesizing 7-hydroxy 4-metbyl coumarin by Pechmann condensation of resorcinol with ethyl acetoacetate are carried out using FLSZ catalyst. The reactions are carried out in high pressure autoclave of 100 ml capacity. The autoclave is equipped with a 45° inclined four bladed pitched turbine impeller, temperature controller (± 1°C), pressure indicator (kg/cm2) and speed regulator (± 5 rpm). Temperature of the reaction is studied in the range of 140 °C to 170 °C (Table 3). The reactor is loaded with about 3.3 g (0.03 mol) of resorcinol, 11.7 g (0.09 mol) of ethyl acetoacetate, 1.5 g FLSZ catalyst (0.03 g/cm3), 1 ml diphenyl methane as internal standard and 36 ml of toiuene to make up the reaction volume up to 50 ml. The samples are taken out after 3 h and analyzed on gas chromatography equipped with 10% OV 17 packed column and flame ionization detector. Table 3; Sr. no; T (°C) Reaction time (h) Catalyst loading (g/cm3 of reactants) Conversion of resorcinol (%) 5 140 3 0.03 50.75 6 150 3 0.03 61.13 7 160 3 0.03 65.89 8 170 3 0.03 72.46 EXAMPLE 9 Friedel-Crafts benzylation of toluene is carried out using FRSZ and FLSZ catalyst. The reaction was conducted in a glass reactor of 5 cm i.d. and 10 cm height with four glass baffles and a four-bladed disc turbine impeller located at a height of 0.5 cm from the bottom of the vessel and mechanically agitated with a motor. Reaction mixtures were analyzed by GC (Chemito-8650 model) equipped with 4 m 10% OV-17 stainless steel column in conjunction with FID detector. Products were confirmed by GC-MS analysis (Perkin Elmer model). 0.5 mol of toluene was reacted with 0.05 mol of benzyl chloride at 90 °C with 0.018 g/cm3 catalyst loading, and 1000 rpm speed of agitation. Table 4 - Catalyst Reaction Time % Conversion of benzyl chloride FLSZ 1 h 85% FRSZ lh 84% CLAIMS We claim, 1. A super acidic catalyst composition comprising of at least 20-70 mass percent metal, 25-60 mass percent of oxygen and 0.5 to 20 mass percent of sulphur prepared via combustion synthesis method. 2. A super acidic catalyst composition as claimed in claim 1 wherein, super acidic catalyst composition have surface area in the range of 1 to 1000 m /g. 3. A super acidic catalyst composition as claimed in claim 1 wherein, super acidic catalyst composition have pore diameter in the range of 2 to 25 nm and pore volume in the range of 0.01 to 3 cm3/g 4. A super acidic catalyst composition as claimed in claim 1 wherein, metal is Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof. 5. A super acidic catalyst composition as claimed in claim 1 wherein, metal is preferably Zr, Al, Ti, Ce and/or mixture thereof. 6. A process for synthesis of a super acidic catalyst composition comprises: a. forming a substantially homogeneous, aqueous precursor mixture containing atleast one substantially water soluble metal salt precursor and a substantially water soluble combustible organic fuel b. heating the said aqueous precursor mixture to form a substantially homogeneous combustible gel c. auto igniting and combusting the gel to produce the metal oxide d. sulfation of the metal oxide with atleast one sulfating agent to deposit sufficient sulphate species e. calcinating the acid treated metal oxide 7. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, metal salt precursor is in the form of nitrate, sulphate, oxynitrate, isopropoxide, formate, carbonate, bicarbonate, acetate, oxyhalide, hydroxide and/or mixture thereof. 8. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, water soluble combustible organic fuel is urea, citric acid, carbohydrazide, oxalyldihydrazide, malonic acid hydrazide, tetraformal trisazine, methyl acetate, ammonium citrate, ammonium nitrate, ammonium tartarate, amino acids and/or mixture thereof. 9. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, water soluble combustible organic fuel is preferably urea, glycine, citric acid, carbohydrazide and/or mixture thereof 10. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, aqueous precursor mixture contains fuel to metal salt mole ratio in the range of0.05to5. 11. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, aqueous precursor mixture contains fuel to metal salt mole ratio preferably in the range of 0.2 to 3. 12. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, aqueous precursor mixture is continuously stirred at least 35 °C for atleast 1 min to form a combustible gel. 13. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, combustible gel is auto ignited to at least 50 °C for minimum 30 sec to form the metal oxide. 14. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, metal oxide is treated with a sulfating agent in the temperature range of 0 to 200 °C for at least 1 h. 15. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, metal oxide is treated with a sulfating agent preferably in the temperature range of 60 to 150 °C. 16. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, sulfating agent is H2S04, (NHO2SO4, H2S, S02, S03, (NH4)2S, C1S03H or CS2. 17. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, sulfation is carried out either in solution or in gaseous phase. 18. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, acid treated metal oxide is calcinated in the temperature range of 200 to 800 °C for atleast 30 min.

Full Text

FORM2
THE PATENTS ACT, 1970 (39 of 1970)
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
"COMBUSTION SYNTHESISED ZIRCONIA AS MATERIAL AND CATALYST"
2. APPLICANT
NAME : YADAV GANAPATI DADASAHEB
(Last Name/Surname) (First Name) (Father's Name/Middle Name)
NATIONALITY: INDIAN
ADDRESS : CHEMICAL ENGINEERING DEPARTMENT,
INSTITUTE OF CHEMICAL TECHNOLOGY
(DEEMED UNIVERSITY),
NATHALAL PARIKH MARG,
MATUNGA (EAST)
MUMBAI 400 019
INDIA
The following specification particularly describes the invention and the manner in which is to
be performed.

FIELD OF THE INVENTION
The present invention relates to a new heterogeneous super acidic catalyst for use in various acid catalyzed reactions of organic compounds for expected shape selectivity, in the mesoporous range and its method of manufacture. The catalyst of the present investigation's in the field of solution combustion synthesis of metal oxides and particularly relates to preparation of superacidic sulphated metal oxides via solution combustion synthesis route.
BACKGROUND OF INVENTION
The use of highly acidic catalysts is very rampant in chemical and refinery industries, and those technologies employing highly corrosive, hazardous and polluting liquid acids are being replaced with super acidic catalysts. Of late, a number of organic syntheses have been conducted with solid acids leading to better chemo-, regio- and stereo- selectivity. In industrial catalytic reaction, it is highly desirable to have high density of surface exposed to active sites in reactor volume. New technologies and recipes are evolving everyday which synthesize catalysts with increased number of active sites.
Preparation, characterization and catalytic investigations of sulfated metal oxides elicited an almost unique interest in the past decade. The beginning of this extraordinary effort was in 1979, when Arata et al. reported in Journal of Chemical Society Chemical Communication (1979), 1148 that zirconia upon proper treatment with, sulfuric acid or ammonium sulfate, exhibits acidity 104 times stronger than that of 100% sulfuric acid
United States patent 3,032,599 is one of the first patents to disclose synthesis of sulfated zirconia catalyst and its application in isomerization and alkylation reaction. In this method zirconia gel is prepared by precipitation of zirconyl salt in water by addition of base. The obtained zirconia gel is then sulfated using ammonium sulfate and activated by calcination at 500 °C. The catalyst showed acid catalytic properties but not satisfactory due to low sulfur content.

United States patent 4,873,017 discloses the method of preparation of anion bound metal oxide catalyst in which the anion can be S04, BF3, CO3, BO3, HPO4, M0O4, B4O7 or PF6 and metal oxide can be zirconium oxide, nickel oxide, aluminium oxide, tin oxide, magnesium oxide, rubidium oxide, titanium oxide or thorium oxide. In the method to prepare sulfate modified zirconium oxide, zirconium hydroxide is prepared by hydrolysis of zirconium oxychloride with ammonium hydroxide. The hydroxide is treated with sulphuric acid followed by calcination at 600°C. The catalyst showed 2-3 % w/w sulfur and excellent activity towards alkoxylation of active hydrogen compounds like primary and secondary alcohols.
Japanese patent 56033037 discloses a method for synthesis of sulfated metal oxide catalyst of high acidity used for isomerization and alkylation. In this method hydroxide or oxide of iron is treated with a solution containing sulfuric acid group, such as sulfuric acid, ammonium sulfate etc. by scattering or immersion, then it is dried and calcined so as to activate it thereby manufacturing a catalyst which is used for isomerization or alkylation in petroleum refining or petro chemistry. The catalyst hereby manufactured allows performing isomerization and alkylation without causing corrosion of the apparatus.
United States patent 5,182,247 discloses a method of preparation of sulfated metal oxide in which the metal oxide was impregnated with a solution of concentrated sulfuric acid dissolved in deionized water. The impregnated catalyst was dried overnight and calcinated at 620°C. Analysis of this material showed it to contain 3.29 % w/w sulfur.
United States patent 5,786,294 discloses a method to produce a sulfated zirconia catalyst in which a mixture of hexadecane amine and DI water is heated and added to another mixture of zirconium isopropoxide, acetyl acetone and anhydrous ethanol. The above mixture is stirred vigorously and precipitate is filtered out. The separated solid is extracted with ethanol and - - soaked into sulfuric acid. The solids are dried and calcinated to get an active catalyst. The catalyst showed pore diameter in the range of 2.5 to 4.7 nm and tetragonal phase with BET surface area in the range of50m2/gto 150m2/g.

United States patent 5,036,035 discloses a method to produce a wide variety of supported sulfated metal oxide catalyst in which at least one member is selected from group VIII metals on a support consisting of hydroxides and oxides of group IV metals and group III metals and mixture thereof. In this method zirconium hydroxide is prepared from precipitation of zirconium oxychloride with aqueous ammonia followed by drying. This support is impregnated with aqueous solutions of chloroplatinic acid, drying and treatment with sulphuric acid. The material is calcinated at 650°C to get an active catalyst.
United States patent 5,719,097 discloses a method to produce a catalyst comprising a hydrogenation/dehydrogenation component, such as a noble metal and an acidic solid component comprising a group IVB metal. In this method zirconium hydroxide is prepared from precipitation of zirconium oxychloride with aqueous ammonia followed by drying. The dried hydroxide was impregnated via incipient wetness method with an aqueous solution containing ammonium metatungstate. The resulting material is dried and calcinated to get an active catalyst.
United States patent 6,448,198 Bl discloses a method of preparation of sulfated metal oxide in which alumina support is impregnated with a solution of zirconium oxychloride, ammonium chloride and water. The impregnated mixture is dried and calcinated prior to sulfation with sulphuric acid. The sulfated mass is dried and platinum is deposited using chloroplatinis acid solution. Drying and calcination of the material resulted into final catalyst.
The previous art of zirconia and related sulfated metal oxide catalysts have associated with them a number of deficiencies resulting from their microporous nature and lower sulfur content. The pore structure can be determinative of catalyst stability and/or activity. Various attempts have been made to synthesize sulfated zirconia with pores in mesoporous range. Use of charged template is reported in Catalysis Letters (1996), 38, 219. But removal of template by calcination -caused this material to collapse. Use. of cationie surfactant was reported in Journal of Material Chemistry (1996), 6, 89. This material showed mesoporosity but with very wide pore size distribution (width at half height
mesoporous material, the neutral templating method, which uses long-chain primary alkyl amines as template.
All these methods have used an approach in which the:metal hydroxide is prepared from metal salt by hydrolysis with a base followed by acid treatment and calcination. Use of combustion synthesized metal oxides in preparation of sulfated metal oxides has not been reported yet. The method of combustion synthesis was first reported in Combustion and Flame (1969), 13(2), 143-56. The combustion synthesis method explores an exothermic, generally very fast and self-sustaining chemical reaction between the desired metal salts and a suitable organic fuel, which is ignited at a temperature much lower than the actual phase formation temperature. Its key feature is that the heat required to drive the chemical reaction and accomplish the compound synthesis is supplied by the reaction itself and not by an external source.
United States patent 6,761,866 Bl discloses a method of combustion synthesis for the synthesis of nanoparticles of a phase pure ceramic oxide of a single component system which includes preparing a solution containing the metal ion by dissolving a salt of the metal ion in an organic solvent or in water. A complexing agent is added in this solution keeping the ratio of charges of the metal ion as unity. Addition of nitric acid and ammonia or nitric acid and ammonium hydroxide is done in order to adjust nitrate and ammonia content of solution followed by heating at 250 °C to 300 °C to produce foam which subsequently ignites to produce combustion product comprising nanoparticles.
United States patent 5,114,702 discloses the method of producing mixed metal oxide using combustion synthesis method in which metal nitrates and organic fuel are dissolved in minimum quantity of deionized water. The mixture is heated on a hot plate to form a concentrated combustible solution which is further heated in a small quantity to approximately 200 °C. The product was formed on. auto ignition which was calcined to remove volatile residuals.
US patent application US 2005/0095194 A1 discloses a method of producing zinc oxide in which zinc nitrate and glycine were mixed in predetermined amount in deionized water o form a homogenous solution with constant stirring. The mixture was heated on a hot plate to transform

it into combustible gel. The gel was heated up to its auto ignition temperature to form zinc oxide nanoparticles. Use of carbohydrazide as a fuel and nitric acid as an additive has also been reported.
All these methods have reported synthesis of metal oxides using combustion synthesis method involving an exothermic reaction between metal salt and fuel. But use of combustion synthesized metal oxide is synthesis of sulfated metal oxide catalyst and their use as catalytic material has not been reported yet.
OBJECTIVE OF INVENTION
It is the objective of present invention to provide a heterogeneous solid acid catalyst possessing high sulfur content, high acidity and mesoporosity with high selectivity towards bulky molecules.
Yet another objective of the present invention is directed to providing for a superacidic metal oxide catalyst via combustion synthesis route to achieve desired mesoporosity and narrow pore size distribution.
Another objective of present invention is to design a superacidic catalyst with retention of tetragonal phase,
Another objective of the present invention is to design catalyst having sulfur content in the range of0.5to20%w/w.
Another objective of the present invention is to design catalyst having specific surface area in the - -range 1 m2/g..to-1000 m2/g, pore diameter in the range of 2 to 25 nm and pore volume in the-range of 0.01 to 3 cmVg.
SUMMARY OF THE INVENTION

The present invention provides a simple method of solution combustion synthesis for preparation
of sulfated metal oxide catalysts in which the metal can be Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe
and/or mixture thereof. The said solid acid catalyst has metal oxide as a basic composition and at
least 0.5 to 20 % w/w of sulphur in the form of sulfate wherein catalyst specific surface area is in
the range 1 m2/g to 1000 m2/g.
BRIEF DESCRIPTION OF DRAWINGS
Drawing I: SEM (Scanning Electron Microscope) images of fuel lean sulfated zirconia (FLSZ)
and fuel rich sulfated zirconia (FRSZ)
Drawing 2: NH3-TPD (Temperature Program Desorption) of fuel lean sulfated zirconia (FLSZ)
and fuel rich sulfated zirconia (FRSZ)
Drawing 3: FT-IR (Fourier transform Infra red) graph for fuel lean sulfated zirconia (FLSZ) and
fuel rich sulfated zirconia (FRSZ)
Drawing 4: Pore size distribution of fuel lean zirconia, fuel rich zirconia, fuel lean sulfated
zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ)
Drawing 5: XRD (X-Ray Diffraction) Analysis of zirconia, fuel lean sulfated zirconia (FLSZ)
and fuel rich sulfated zirconia (FRSZ)
DETAILED DESCRIPTION OF INVENTION
International Union of Pure and Applied Chemistry (IUPAC) define pores having width in the range of 2 nm to 50 nm as mesopores and those with width less than 2 nm are micropores. For catalytic processes involving bulky reactants, pore dimensions of greater than 2 nm are required for better shape selectivity. The pore structure of sulfate modified metal oxides is largely controlled by the preparation method and calcination temperature. The conventional precipitation - method results into microporous material which is mere suitable for reactions of small molecules in the vapor phase. To form a catalyst that has shape selectivity for larger molecules, mesoporous material with narrow pore-size distributions needs to be created.

The amount of sulphur loading decides the acidity and activity in sulfated metal oxide catalyst. In sulfated zirconia catalyst the retention of tetragonal phase is necessary for better activity of catalyst. It is a challenge to achieve higher sulphur loading with retention of tetragonal phase as sulphur loading above 4 % results into generation of secondary monoclinic phase along with major tetragonal phase. Very high sulfur loading results in formation of metal sulfates instead of sulfated metal oxide. All previous literature suggests that S-Z1O2 has been prepared so far with a maximum 9% w/w of sulfur with preservation of the tetragonal phase of zirconia and above this value the tetragonal phase is strongly affected.
In recent years, combustion synthesis has emerged as a powerful alternative for material synthesis. This method is highly reproducible, less time consuming and does not involve multi step synthesis. This method produces fine nano scale metal oxides with high surface area and
synthesis method explores an exothermic, generally very fast and self-sustaining chemical reaction between the desired metal salts and a suitable organic fuel, which is ignited at a temperature much lower than the actual phase formation temperature. Here the metal salts can be nitrates, acetates etc. whereas the frequently used fuels are glycine, urea and carbohydrazide. Its key feature is that the heat required to drive the chemical reaction and accomplish the compound synthesis is supplied by the reaction itself and not by any external source.
The fuel to oxidizer ratio governs the surface properties of combustion synthesized metal oxides. When the fuel and oxidizer are in stoichiometric amount, neither atmospheric oxygen is required for combustion nor it is evolved in the combustion. When the fuel to oxidizer ratio is lower than the stoichiometric composition, then the precursor mixture is called fuel lean composition and when the fuel to oxidizer ratio is higher than stoichiometric ratio it is called fuel rich composition. At fuel lean composition, the adiabatic flame temperature is low due to comparatively less-fuel--which results into comparatively less sintering of material which enhances the surface area. On the other hand the amount of gasses evolved is less compared to fuel rich composition which results into lowering of surface area. At fuel rich composition though the amount of gas evolution is substantially higher, higher flame temperature results into sintering of material. All these factors make it difficult to predict the surface area variation with

fuel to oxidizer ratio. It is observed that the surface area is higher in fuel lean and fuel rich conditions compared to stoichiometric conditions. Hence for catalytic applications, it is always advisable to operate in fuel lean or fuel rich composition.
The heterogeneous catalyst of the present invention is calcinated catalyst composition which comprising at least 20-70 mass percent metal, 25-60 mass percent of oxygen and 0.5 to 20 mass percent of sulphur prepared via combustion synthesis method.
Thus resultant calcinated catalyst composition has surface area in the range of 1 to 1000 m2/g, pore diameter in the range of 2 to 25 nm and pore volume in the range of 0.01 to 3 cm3/g.
One of embodiments of the invention is that in the calcinated catalyst composition, metal ion is Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof.
One of embodiments of the invention is that in the calcinated catalyst composition, metal ion is preferably Zr, Al, Ti, Ce and/or mixture thereof.
One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, metal ion precursor used are in form of nitrate, sulphate, oxynitrate, isopropoxide, formate, carbonate, bicarbonate, acetate, oxyhalide, hydroxide and/or mixture thereof.
One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, the metal ion precursor used is preferably nitrate and oxynitrate.
One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, fuel used is urea, citric acid, carbohydrazide, oxalyldihydrazide, malonic acid hydrazide, tetraformal trisazine, methyl -acetate, ammonium citrate, ammonium nitrate, ammonium tartarate, amino acids and/or mixture thereof.

One of embodiments of the invention is that in the process for synthesis of a super acidic catalyst composition, fuel used is preferably glycine, citric acid urea, carbohydrazide and/or mixture thereof.
General method for production of calcinated catalyst composition comprises
a. forming a substantially homogeneous, aqueous precursor mixture containing
atleast one substantially water soluble metal salt precursor and a substantially
water soluble combustible organic fuel
b. heating the said aqueous precursor mixture to form a substantially homogeneous
combustible gel
c. auto igniting and combusting the gel to produce the metal oxide
d. sulfation of the metal oxide with atleast one sulfating agent to deposit sufficient
sulphate species
e. calcinating the acid treated metal oxide
The activity of the catalyst is tested for Pechmann condensation reaction between resorcinol and ethyl acetoacetate and also for Friedel Craft's benzylation of toluene.
In further accord with the present invention, the catalyst comprises of sulfate modified oxides of Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof. This heterogeneous catalyst is separated from the reaction mixture by filtration.
EXAMPLE 1: FUEL LEAN SULFATED ZIRCONIA CATALYST PREPARATION
In fuel lean sulfated zirconia catalyst (FLSZ), the mole ratio of zirconium oxynitrate hexahydrate [ZrO(N03)2.6H20] and glycine is less than the stoichiometric mole ratio. In synthesis of this catalyst, the initial mixture contains glycine and zirconium oxynitrate hexahydrate in 1:2 molar ratio. In the method to synthesize around 3 g of fuel lean sulfated zirconia catalyst, 1 g of glycine and 9 g of zirconium oxynitrate hexahydrate are diluted in 20 ml of Dl water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace

maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline zirconium dioxide powder. This material is immersed in 15 cm3/g of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating is started to evaporate the solvent. This material is kept in oven at 120 °C for 24 h and calcined at 650 °C for 3 h to get around 3 g of the active catalyst FLSZ.
EXAMPLE 2: FUEL RICH SULFATED ZIRCONIA CATALYST PREPARATION
In fuel rich sulfated zirconia catalyst (FRSZ), the mole ratio of zirconium oxynitrate hexahydrate [ZrO(N03)2.6H20] and glycine is higher than the stoichiometric mole ratio. In synthesis of this catalyst, the initial mixture contains glycine and zirconium oxynitrate hexahydrate in 2:1 molar ratio. In the method to synthesize around 3 g of fuel lean sulfated zirconia catalyst (glycine to nitrate mole ratio = 2), 4 g of glycine and 9 g of zirconium oxynitrate hexahydrate are diluted in 25 ml of DI water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline zirconium dioxide powder. The oxide with fuel rich initial composition consist considerable amount of residual carbon. To remove this unwanted carbon, the zirconium dioxide powder is calcined at 550 °C for 4 h prior to acid treatment. The material is then immersed in 15 cmVg of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating started to evaporate the solvent. This material is kept in the oven at 120 °C for 24h and calcined at 650 °C for 3 h to get around 3 g of the active catalyst FRSZ.
FLSZ and FRSZ are characterized by following techniques
Drawing 1: SEM (Scanning Electron Microscope) images of fuel lean sulfated zirconia (FLSZ)
and fuel rich sulfated zirconia (FRSZ)
Drawing 2: NH3-TPD (Temperature Program Desorption) of fuel lean sulfated zirconia (FLSZ)
and fuel rich sulfated zirconia (FRSZ)

Drawing 3: FT-IR graph for fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia
(FRSZ)
Drawing 4: Pore size distribution of fuel lean zirconia, fuel rich zirconia, fuel lean sulfated
zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ)
Drawing 5: XRD Analysis of zirconia, fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated
zirconia (FRSZ)
EDX results are as follows Table 1

Element FLSZ(%) FRSZ(%)
O 38.8 38.6
S 15.14 15.1
Zr 46.05 46.3
Both the catalysts showed substantially high sulfur content (S > 15 % w/w)
ASAP results are as follows Table 2

Surface area (m2/g) Pore Size
A° Pore Volume Cm3/g
FLSZ 53.26 98.48 0.131
FRSZ 21.63 91.43 0.051
Both catalysts showed pore size in the mesoporous range.
EXAMPLE 3 SULFATED TITANIA CATALYST PREPARATION
In the method to synthesize around 3 g of sulfated titania (SCVVTiOi) catalyst, 3.96 g of glycine and 9 g of titanyl nitrate [TiO(NO3)2] are diuted in 25 ml of DI water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The

viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline titanium dioxide powder. The material is then immersed in. 15 cm3/g of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating started to evaporate die solvent. This material is kept in the oven at 120 °C for 24h and calcined at 550 °C for 3 h to get around 3 g of the active catalyst sulfated titania.
EXAMPLE 4 SULFATED CERIA ZIRCONIA CATALYST PREPARATION
In the method to synthesize around 3 g of sulfated ceria zirconia (SO^VCeo.sZro.sOi) catalyst, 3.24 g of carbohydrazide, 5 g of Ce(N03)3.6H20 and 3.9 g of Zr(N03)2.6H20 diuted in 25 ml of DI water. The solution is stirred on a magnetic stirrer at 80 °C for 3h to transform the aqueous solution into a highly viscous gel. The viscous gel is then transferred into a silica crucible and kept in a muffle furnace maintained at 350 °C. The gel undergoes self ignition and gets transformed into a fluffy mass. Mild crushing of the fluffy mass resulted into a fine crystalline Ceo.5Zro.5O2 powder. The material is then immersed in 15 cm3/g of 1 M chlorosulfonic acid in ethylene dichloride. Without allowing moisture absorption the material is transferred in an oven and the heating started to evaporate the solvent. This material is kept in the oven at 120 °C for 24 h and calcined at 650 °C for 3 h to get around 3 g of the active catalyst SO427Ce0.5Zr0.5O2.
EXAMPLE 5-8
A series of reactions for synthesizing 7-hydroxy 4-metbyl coumarin by Pechmann condensation of resorcinol with ethyl acetoacetate are carried out using FLSZ catalyst. The reactions are carried out in high pressure autoclave of 100 ml capacity. The autoclave is equipped with a 45° inclined four bladed pitched turbine impeller, temperature controller (± 1°C), pressure indicator (kg/cm2) and speed regulator (± 5 rpm). Temperature of the reaction is studied in the range of 140 °C to 170 °C (Table 3). The reactor is loaded with about 3.3 g (0.03 mol) of resorcinol, 11.7 g (0.09 mol) of ethyl acetoacetate, 1.5 g FLSZ catalyst (0.03 g/cm3), 1 ml diphenyl methane as internal standard and 36 ml of toiuene to make up the reaction volume up to 50 ml. The samples

are taken out after 3 h and analyzed on gas chromatography equipped with 10% OV 17 packed column and flame ionization detector.
Table 3;

Sr. no; T
(°C) Reaction time (h) Catalyst loading (g/cm3 of reactants) Conversion of
resorcinol
(%)
5 140 3 0.03 50.75
6 150 3 0.03 61.13
7 160 3 0.03 65.89
8 170 3 0.03 72.46
EXAMPLE 9
Friedel-Crafts benzylation of toluene is carried out using FRSZ and FLSZ catalyst. The reaction was conducted in a glass reactor of 5 cm i.d. and 10 cm height with four glass baffles and a four-bladed disc turbine impeller located at a height of 0.5 cm from the bottom of the vessel and mechanically agitated with a motor. Reaction mixtures were analyzed by GC (Chemito-8650 model) equipped with 4 m 10% OV-17 stainless steel column in conjunction with FID detector. Products were confirmed by GC-MS analysis (Perkin Elmer model). 0.5 mol of toluene was reacted with 0.05 mol of benzyl chloride at 90 °C with 0.018 g/cm3 catalyst loading, and 1000 rpm speed of agitation.
Table 4

- Catalyst Reaction Time % Conversion of benzyl chloride
FLSZ 1 h 85%
FRSZ lh 84%

CLAIMS
We claim,
1. A super acidic catalyst composition comprising of at least 20-70 mass percent metal, 25-60 mass percent of oxygen and 0.5 to 20 mass percent of sulphur prepared via combustion synthesis method.
2. A super acidic catalyst composition as claimed in claim 1 wherein, super acidic catalyst composition have surface area in the range of 1 to 1000 m /g.
3. A super acidic catalyst composition as claimed in claim 1 wherein, super acidic catalyst composition have pore diameter in the range of 2 to 25 nm and pore volume in the range of 0.01 to 3 cm3/g
4. A super acidic catalyst composition as claimed in claim 1 wherein, metal is Zr, Al, Ti, Si, Ce, Sn, Zn, La, Co, Fe and/or mixture thereof.
5. A super acidic catalyst composition as claimed in claim 1 wherein, metal is preferably Zr, Al, Ti, Ce and/or mixture thereof.
6. A process for synthesis of a super acidic catalyst composition comprises:
a. forming a substantially homogeneous, aqueous precursor mixture containing
atleast one substantially water soluble metal salt precursor and a substantially
water soluble combustible organic fuel
b. heating the said aqueous precursor mixture to form a substantially
homogeneous combustible gel
c. auto igniting and combusting the gel to produce the metal oxide
d. sulfation of the metal oxide with atleast one sulfating agent to deposit
sufficient sulphate species
e. calcinating the acid treated metal oxide

7. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, metal salt precursor is in the form of nitrate, sulphate, oxynitrate, isopropoxide, formate, carbonate, bicarbonate, acetate, oxyhalide, hydroxide and/or mixture thereof.
8. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, water soluble combustible organic fuel is urea, citric acid, carbohydrazide, oxalyldihydrazide, malonic acid hydrazide, tetraformal trisazine, methyl acetate, ammonium citrate, ammonium nitrate, ammonium tartarate, amino acids and/or mixture thereof.
9. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, water soluble combustible organic fuel is preferably urea, glycine, citric acid, carbohydrazide and/or mixture thereof
10. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, aqueous precursor mixture contains fuel to metal salt mole ratio in the range of0.05to5.
11. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, aqueous precursor mixture contains fuel to metal salt mole ratio preferably in the range of 0.2 to 3.
12. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, aqueous precursor mixture is continuously stirred at least 35 °C for atleast 1 min to form a combustible gel.
13. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, combustible gel is auto ignited to at least 50 °C for minimum 30 sec to form the metal oxide.

14. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, metal oxide is treated with a sulfating agent in the temperature range of 0 to 200 °C for at least 1 h.
15. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, metal oxide is treated with a sulfating agent preferably in the temperature range of 60 to 150 °C.
16. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, sulfating agent is H2S04, (NHO2SO4, H2S, S02, S03, (NH4)2S, C1S03H or CS2.
17. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, sulfation is carried out either in solution or in gaseous phase.
18. A process for producing a super acidic catalyst composition as claimed in claim 6 wherein, acid treated metal oxide is calcinated in the temperature range of 200 to 800 °C for atleast 30 min.

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Patent Number

268910

Indian Patent Application Number

16/MUM/2011

PG Journal Number

39/2015

Publication Date

25-Sep-2015

Grant Date

22-Sep-2015

Date of Filing

04-Jan-2011

Name of Patentee

YADAV GANAPATI DADASAHEB

Applicant Address

CHEMICAL ENGINEERING DEPT., INSTITUTE OF CHEMICAL TECHNOLOGY (DEEMED UNIVERSITY), NATHALAL PARIKH MARG, MATUNGA (E), MUMBAI-400 019, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	YADAV GANAPATI DADASAHEB	CHEMICAL ENGINEERING DEPT., INSTITUTE OF CHEMICAL TECHNOLOGY (DEEMED UNIVERSITY), NATHALAL PARIKH MARG, MATUNGA (E), MUMBAI-400 019, INDIA.
2	AJGAONKAR NAISHADH PRADEEP	YADAV GANAPATI DADASAHEB CHEMICAL ENGINEERING DEPT., INSTITUTE OF CHEMICAL TECHNOLOGY (DEEMED UNIVERSITY), NATHALAL PARIKH MARG, MATUNGA (E), MUMBAI-400 019, INDIA.

PCT International Classification Number

B01J21/06

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA