Indian Patents. 215581:A PROCESS FOR THE PREPARATION OF SUPPORTED SOLID CATALYSTS USEFUL FOR FRIEDEL-CRAFTS REACTIONS.

Title of Invention	A PROCESS FOR THE PREPARATION OF SUPPORTED SOLID CATALYSTS USEFUL FOR FRIEDEL-CRAFTS REACTIONS.
Abstract	The present invention relates to a process for the preparation of supported solid catalyst useful for Friedel Crafts reaction. The present invention provides the preparation of supported solid catalyst comprising of mixed metal oxides or halides deposited on porous catalyst carriers or supports useful for heterogeneously or solid catalyzed Friedel-Crafts reaction.

Full Text	This invention relates to a process for the preparation of supported catalysts useful for the Friedel-Crafts reactions. This invention particularly relates to a process for the preparation of supported solid catalysts, comprising of mixed metal oxides or halides deposited on porous catalyst carriers or supports, useful for the heterogeneously or solid catalyzed Friedel-Crafts reactions. The process of this invention could be used for the preparation of solid catalysts useful in the Friedel-Crafts reactions. A number of homogeneous and heterogeneous acidic catalysts useful for the Friedei-Crafts reactions, for example alkylation, polyalkylation, aralkylation, acylation, aroylation and the like, are known in the prior art. Homogeneous Catalysts for Friedel-Crafts Reactions The acylation and benzoylation of aromatic compounds and related Friedel-Crafts type reactions using homogeneous lewis acid catalysts are well-known in the prior an [ref. G. A. Olah. in Friedel-Crafts and related reactions: vol. Ill, Acylation and related reactions, Wiley-Interscience PubL New York, 1964] A use of CuCh as a homogeneous catalyst in the benzylation of benzene or substitute: be-zenes b> benzyl chloride is disclosed in two US patens: TJ.S. 3,678,122(1972) and L'.S 3,679,760(1972). A French patent, Fr. Demande 2.144.578(1973), disclosed nenzylation of p substituted ohenols by benzyl hali.l.s in .he oresence of homogeneous Zr.Ch catalyst. - •. USSR patent, L.S.S.R. 394,353(197 ), disclosed a use of SnSCu or SnC '•-, as :., :iogeneous catalyst for the benzylation with benzyl chloride of m-dimethoxy benzene. A Japanese patent. Japan Kokai 7399,154(1973), disclosed preparation of dibenzyl benzene derivatives by benzylation of benzene or substituted benzenes using AlCl3, FeCb and 98% IbSO4. A use of H2SO4 or H3PO4 and optionally 4-CH3CoH4SO3H, ZnCl2, BF3, etc. in the preparation of c- benzyltoluenes by the reaction of a o-chloromethyltoluene with a benzene derivative is disclosed in a German patent, Ger. Offen 2,456,747 (1976). A use of phosphoric acid and optionally H2S04 or a Friedel-Crafts type metal halide in the benzylation of benzene with benzylether is disclosed in a US Patent, U.S. 4,049,733 (1977). A German patent, Ger.offen 2,451,037 (1976), disclosed the use of HF as a catalyst for the benzoylation of aromatic compounds. A French patent, Fr. Demande FR 2,496,097 (1982) disclosed the acylation of benzene by phthaleic anhydride using HF-BFa mixture. More recently, an European Patent, Eur.Pat.Appl.EP 538,704 (1993), disclosed a process for the preparation of p-substituted o-benzylphenols by treating phenols. p-R GjH4OH (R = halo, alkyl, OH, alkoxy, alkylmercapto, aryl, aryloxy or arylmercapto), with ArCH:X (Ar = corresponding aryl nucleus; X = halo, arylcarboxy, phenylsulfatoxy, hydroxy. alkoxy etc.) in a continuously functioning distillation apparatus in the presence of dissolved acid catalyst. The main disadvantages of the use of homogeneous acid catalyst for the Friedel-Crafts processes are as follows: 1) The separation and recovery of the dissolved acid catalysts from the hqu: : reaction mixture is diffici.it. 2) The disposal of the used acid catalys' • creates environmental pollution. 3) The homogeneous acid ca ~:;. ts also lose several other problems such as high toxicity, corrosion, spent acid disposal and use of more than the stoichiometric amount. Heterogeneous Catalysts for Friedel-Crafts Reactions A German patent, Ger.Offen 2,547,030 (1977), disclosed the preparation of o-benzyltoluenes by the reaction of o-methylbenzyl halides with substituted benzenes in the presence of Al-silicate. The 2-CH3C6H4CH2Cl was stirred with toluene and Al-silicate (25%Al2O3) at 110°C to give 81% 2-methylbenzyltoluene. According to a Japanese patent. Jpn. Kokai Tokkyo Koho JP 59,186,937 (1984), o-benzylphenol was prepared by the liquid phase reaction of benzyl alcohol with phenol in the presence of y-A^Oa. For example 7.5 g y-AhCh was added to a mixture of 32.5 g benzyl alcohol and 47 g phenol at 190°C under stirring to give a product containing 49.9% o-benzylphenol. A German Patent, Ger. Offen DE 3.700,917 (1988), disclosed the preparation of p-substituted o-benzylphenols by benzylation of p-substituted phenols with benzylalcohol in the presence of Na-Y type zeolite. A mixture of 0.5 mole 4-ClC6H4OH, 0.1 mole C0H5CH2OH and 0.6 g of Na-Y type zeolite was heated at 200°C for 3 hrs to give 25.4 % 2-benzyl-4-chlorophenol. A French patent, Fr. Demande FR 2,667,063 (1992), disclosed the preparation of 4-substituted benzophenones by aroylation of substituted benzenes by substituted benzoic acid in the presence of HY and HP type zeolites. Accordingly 4-C1 C6H4COOH and PhMe were heated 4 h at 200°C under 2 x 10" Pa in the presence of calcined zeolite HB to give 84.4% 4-(4-ClC6H4CO)C6H4Me. A recent paper by Vincent et al. (ref. Tetrahedron Lett. 35, 1994, 2601), disclosed that H-ZSM-5 zeolite can catalyze the benzoylation by benzoyl chloride of phenol and anisole but not the benzoylation with benzoyl chloride of benzene , halobenzene and naphthalene, at 120°Cfor5h. A German patent, Ger. Offen DE 3,836,780 (1990), disclosed the process for the preparation of benzylbenzenes from benzenes and benzyl alcohols in the presence of activated bleaching earth and a diluent at 90-140°C. According to Japanese patent, Jpn Kokai Tokkyo Koho JP 03,170,442 (1991), benzylbiphenyls are manufactured by benzylating biphenyl and diphenylmethane with > 1 compound from benzyl halides, benzyl alcohol, benzyl ether in the presence of a zeolite or silica-alumina catalyst. An European patent, Eur.Pat. appl. EP 428,081 (1991), disclosed a process of benzylation of alkylbenzenes with benzyl chloride in the presence of H-Y or H-L zeolite catalyst. According to a German patent, Ger. Offen DE 4,038,933 (1992), disclosed a process for benzylation of aromatics using technical carbon catalysts. Alkylation, aralkylation, acylation or aroylation of aromatic- compound involves electrophilic substitution of H from the aromatic nucleus of the aromatic compound. It is well known in the prior art that the electrophilic substitution is favoured by the presence of electron donating groups, such as OH, alkyl, alkoxy, phenoxy, amine, alkyl amine, SH etc., in the aromatic compound. Whereas the electrophilic substitution is inhibited by the presence of electron withdrawing groups such as halo, nitro. cyano, carboxy, aldehyde, etc., in the aromatic compound, [ref. G.A.Olah, in Friedei-Crafts and related reactions, Wiiey-Interscience Publ., New York, 1963]. Although some imitations of the homogeneous acu a::ryze; processes are overcome in the prior art heterogeneous catalyzed processes descriDcv: above, the aiicyiating. aralkylating. acylating or aroylating activity of the solid catalysts used in the prior an processes are low, particularly for alkylating, aralkylating, acylating or aroyL.ting aromatic compounds containing electron withdrawing groups. Hence there is a great practical need for finding more efficient solid catalyst for the alkylaiing, aralkylating, acylating or aroylating of aromatic compounds. There is also a need for finding highly efficient solid catalyst also for the alkylating, aralkylating, acylating or aroylating of aromatic compounds containing electron withdrawing groups such as halo, nitro, cyano, carboxy, aldehyde, etc.. This invention is, therefore, made with the following objects so that most of the drawbacks or limitations of the prior art homogeneous and heterogeneous catalyzed processes for the Friedel-Crafts type reactions could be overcome. 1. Accordingly, the main object of this invention is to provide a novel supported catalysts comprising mixed metal oxides or halides, which have high activity for the Friedel- Crafts reactions not only when the aromatic ring activating groups (i.e. electron donating groups such as alkyl, hydroxy, alkoxy, etc) are present in the aromatic ring to be aralkylated, acylated or aroylated but also when the ring activating group is absent or when aromatic ring deactivating groups (i.e. electron withdrawing groups such as halo, nitro, etc) are present in the aromatic ring to be aralkylated, acylated or aroylated. so that the reaction temperature is low and/or time for completing the reaction is short. 2. Another important object of this invention is to provide novel solid catalysts for the heterogeneous Friedel-Crafts reactions, which can be reused repeatedly for the catalytic reactions. Accordingly this invention provides a process for the preparation of supported solid catalysts, useful for the Friedel-Crafts reactions, wherein said catalysts are represented by formula AaMZb(c) / S wherein, A is selected from chemical elements Ga, Al, B, Zn, Fe. Sn, Ti, Th, Zr or a mixture of rwo or more thereof; M is selected from chemical elements In, Tl or a mixture thereof; Z is selected from chemical elements 0, Cl, Br or I; S is porous catalyst support or carrier: a is AM mole ratio in the range of about 0.001 to about 100; b is number of atoms of Z needed to fulfil the valence requirement of the metallic elements AaM present in the supported catalyst; c is weight percentage loading of AaMZb deposited on said catalyst support or carrier (S) in the range of about 0.5 to about 50; wherein said process comprises : (i) depositing on said catalyst support mixed metal halides represented by formula : AaMDd, wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn. Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In, Tl or a mixture thereof; D is chemical group selected from halogen Cl, Br or I or a mixture thereof; a is A/M mole ratio in the range of about 0.001 to about 100; and d is number of atoms of D needed to fulfil the valence requirement of the metallic elements AaM; from non-aqueous moisture-free solvent, in which said mixed metal halides are dissolved, by known catalyst impregnating techniques, such that the weight percent loading of said mixed metal halides on said catalyst support is in the range of about 0.5 wt% to. about 50 wt%; or depositing on said catalyst support mixed metal compounds represented by formula : AaMEe, wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn. Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In, Tl or a mixture thereof; E is chemical group selected from O, NCb, OH, halo, alkoxides or CnH2n+iCOO, wherein n is in the range of 0 to 15; a is A/M mole ratio in the range of about 0.001 to about 100; e is number of groups of E needed to fulfil the valence requirement of the metallic elements AaM; by known catalyst impregnation, coating or co-precipitation techniques, such that the weight percent loading of said catalyst support is in the range of about 0.5 wt% to about 50 wt%, (ii) heating the catalyst mass obtained from the step-i to dryness at a temperature of about 25°C to about 250°C under vacuum or in presence of air or inert gas, (iii) calcining the dried mass obtained from step-ii at a temperature of about 100°C to about 700°C under vacuum or in presence of air or inert gas for about 0.1 h to about 100 h. In the process of this invention, the porous catalyst carrier or support, S, is selected from micro- and/or meso porous zeolites and zeolite-like materials, synthetic and natural clays, silica gel, alumina and meso and/or macroporous catalyst carriers containing SiO:, A1:O?, SiC, ZrO:, HfO2 or a mixture thereof, and more preferably, S is selected from mesoporous zeolites such as high silica MCM-41 and the like, silica gel cation exchange clays such as montmorillonite clay and the like, and chemically inert or sintered low surface area macroporous catalyst carriers or supports containing SiO2, AliOj, SiC, ZrO2, HfC>2 or a mixture thereof. In the process of this invention, a preferred loading of the active catalyst mass (AaMZb, as described above) on the porous catalyst carrier or support (S), c. is from 2 wt% to 20 wt%; the preferred period of catalyst calcination in the step-iii of said catalyst preparation process is from 0.25 h to 25 h: the preferred chemical element A is Ga. Fe. Zn or a mixture thereof; and the preferred chemical element Z is 0 or Cl. The product obtained from the process of this invention is a novel supported solid catalyst comprising of mixed metal oxides or halides deposited on porous catalyst carriers or supports, useful for the Fridel-Crafts reactions such as alkylation, aralkylation. acylation or aroylation of aromatic compounds in the preparation of fine chemicals. In the process of this invention, said mixed metal oxides or halides (AaMZt) are responsible for the catalytic activity and the main roles played by the porous catalyst carrier or support (S) are (i) to disperse the active catalyst components (said metal oxides or halides) uniformly and thereby increasing their surface area, (ii) to avoid sintering of said active catalyst components during the catalyst calcination, (iii) to provide high mechanical strength against crushing and/or abrasion to the catalyst during its use in the reaction and (iv) to ease the filtration of the catalyst from the reaction mixture. The said catalyst without catalyst carrier or support may be used for the Friedel-Crafts reactions but said catalyst with catalyst carrier or support is certainly more preferable. In the process of this invention, the presence of more than one metallic element in said active catalyst mass (AaMZb) is essential for obtaining a synergetic effect, and thereby increasing the catalytic activity of said catalyst. In the process of this invention, said mixed metal compounds (AaMEe) are catalyst precursors which are converted to mixed metal oxides directly by thermal decomposition or by hydrolysis or co-precipitation followed by calcination or decomposition at said calcination conditions. In the process of this invention, the non-aquous solvent used for depositing said mixed metal halides (AaMD;) on said catalyst support may be selected from moisture-free volatile organic solvents such as acetonitrile, methanol, nitromethane, chloroform, and the like. In the process of this invention, said heating step (step-ii) is essential for drying or removing the solvent from the supported catalyst mass obtained in step-i and said calcining step (step-iii) is essential for decomposing said catalyst precursors to corresponding metal oxide or to disperse said mixed metal halides uniformly on the surface of said catalyst carrier or support. Zeolites are crystalline aluminosilicates containing well defined channels or pores of uniform diameter. A large number of microporous zeolites, such as X, Y, mordenite, L, beta. ZSM-5, ZSM-8, ZSM-11, etc., and mesoporous zeolites, such as M41S type material, e.g. MCM-41, are known in the prior-art [ ref. Breck in Zeolite Molecular Sieves, Wiley-Interscience Publ., New York, 1974; Beck and Co-workers. J.Am.Chem.Soc., vol.114, page 10834,year 1992; Nature (London) vol.359, page 710, year 1992]. A number of cation exchange natural and synthetic clays having layered silicate structure are known in the prior art [ref. R. A. Schoonheydt "Clays : From two to three dimensions" in Studies in Surface Science and Catalysis, vol. 58, page 201-238, 1991; and K. Ohtsuka, Chem. Mater., vol. 9, page 2039-2051, year 1997]. In general, micropores have diameter below 1 nm; mesopores have diameter between about 1 nm and about 20 nm; and macropores have diameter above about 20 nm. Said catalyst containing only micropores of this process may be used in the Friedel-Crafts reactions when both the reactants of the reaction have critical size (minimum molecular diameter) less than 0.7 nm. Whereas said catalyst containing meso and/or macropores may be used in the said reactions for reactants having both small and large molecular size. Said catalyst of this invention activates both the reactants of the Friedel-Crafts reactions and thereby shows high activity in the Friedel-Crafts reactions such as alkylation, aralkylation. acylation and aroylation reactions of aromatic compounds containing not only electron donating group, which activates the aromatic ring, but also in the absence of any electron donating group or even containing electron withdrawing group, which deactivates the aromatic ring. The present invention reveals that the said supported solid catalysts comprising mixed metal oxides or halides deposited on porous catalyst carrier or support, showing very high activity in the Friedel-Crafts reactions such as alkylation, aralkylation. acylation and aroylation reactions of aromatic compounds without containing any electron donating group or containing electron donating and/or electron withdrawing groups in their aromatic ring, can be prepared by the catalyst preparation process of this invention. Using these catalysts, the Friedel-Crafts reactions can be carried out at lower temperatures and/or in shorter reaction periods. By using the catalyst of this invention, a complete conversion of benzyl chloride in the benzylation of benzene to diphenyl methane at 80°C and with catalyst/ benzyl chloride wt./wt. ratio of 0.1 and benzene/benzyl chloride mole ratio of 17.0 can be achieved in a reaction period of 8.0 min. The present invention is described with respect to the following examples illustrating the process of this invention for the preparation of said supported solid catalysts useful for the Friedel-Crafts reactions. These examples are provided for illustrative purposes only and are not to be construed as limitations on the process of this invention. The main finding of this invention is that, the said catalysts show high activity in the Friedel-Crafts reactions, such as alkylation, aralkylation, acylation and aroylation reactions not only when the electron donating group, which is aromatic ring activating group, is present in the aromatic ring of the aromatic compound but also when the ring activating group is absent or when the electron withdrawing group, which is aromatic ring deactivating group, is present in the aromatic ring of the aromatic compound, so that the reaction temperature is low and/or the time required for completing the reactions is short. Other important finding of this invention is that said solid catalyst can be separated easily from the reaction mixture and reused repeatedly in the Friedel-Crafts reactions. Yet another important finding of this invention is that the mechanism of the activation of reactants over said solid catalysts is different from that over the acidic catalysts used in the prior art for the Friedel-Crafts reactions. EXAMPLE-1 A supported catalyst : Ga2.27TlO3.9 (10 wt%) / SA5205 was prepared by impregnating a mixture of 2.05 g gallium nitrate and 0.94 g thallous nitrate, dissolved in 10 ml distilled water, on 15 g SA5205 catalyst support ( obtained from M/s. NORTON Co. U.S.A.), having main chemical composition : 11.8 % SiO2, 86.1 % A12O3; surface area A supported catalyst : Fen.zTlCls-jb (10 wt%) / Montmorrilonite KIO was prepared by impregnating a mixture of 0.9 g ferric chloride and 0.1 g thallic chloride, dissolved in 18 ml moisture-free acetonitrile, on 10 g Montmorillonite KIO clay (obtained from Aldrich Chemical Co. U.S.A.) by incipient wetness technique, drying the impregnated rtiass under vacuum at 40°C for 20 h and then calcining or heating further in a flow of nitrogen free from oxygen and traces of moisture at 120°C for l0h. EXAMPLE-3 A supported catalyst : Ga12.6lnCl40.8 (H wt%) / Montmorrilonite KIO was prepared by impregnating a mixture of 0.1 g indium chloride and 1.0 g gallium chloride, dissolved in 17 ml moisture-free methanol, on 10 g Montmorillonite KIO clay (obtained from Aldrich Chemical Co. U.S.A.) by incipient wetness technique, drying the impregnated mass under vacuum at 100°C for 1 h and then calcining or heating further in a flow of pure helium at 150°C for 5 h. EXAMPLE-4 A supported catalyst: Gaio.oInO16.5. (11.8 wt%) / SA5205 was prepared by impregnating a mixture of 2.8 g gallium nitrate and 0.33 g indium nitrate, dissolved in 7 ml distilled water, on 10 g SA5205 catalyst support, described in EXAMPLE-1, by incipient wetness technique, drying the impregnated mass in an air oven at 100°C for 15 h and calcining in air at 600°C for 2 h. The surface area of the catalyst was 3.9 m2g~'. EXAMPLE-5 A supported catalyst : Gau.oInO18.0.(2.3 wt%) / MCM-41 was prepared by impregnating a mixture of 2.8 g gallium nitrate and 0.3 g indium nitrate, dissolved in 100 ml distilled water, on 50 g high silica meso-porous zeolite [prepared by the procedure described in the ref. Choudhary et al., Proceeding of Indian Academy of Sciences, (Chemical Sciences) volume 109, page 229 and year 1997], by incipient wetness technique, drying the impregnated mass in an air oven at 100°C for 20 h and calcining in air at 500°C for 4 h. The surface area of the catalyst was 1102 m~g"'. EXAMPLE-6 A supported catalyst: Zno.o3T10o.53 (20.4 wt%) / SA5205 was prepared by impregnating a mixture of 0.3 g zinc nitrate and 5.0 g thallous nitrate, dissolved in 14 ml distilled water, on 20 g SA5205 catalyst support, described in EXAMPLE-1, by incipient wetness technique, drying the impregnated mass in an air oven at 120°C for 8 h and calcining in air at 550°C for 4 h. The surface area of the catalyst was ~ 0.1 m2g~'. EXAMPLE-7 A supported catalyst: Ga29.0 TlO.44.0 (10.8 wt%) / SiO2 gel was prepared by impregnating a mixture of 14.0 g gallium nitrate and 0.5 g thallous nitrate, dissolved in 50 ml distilled water, on 50 g SiO: gel catalyst support (Fuji Davison, A-type, surface area 720 rn2g"')in powdered form, by incipient wetness technique, drying the impregnated mass in an air oven at 125°C for 6 h and calcining in air at 600°C for 4 h. The surface area of the catalyst was 325 m2g"'. EXAMPLE-8 A supported catalyst : Ga0.05TlOo.jg (5.1 wt%) / SA5205 was prepared by impregnating a mixture of 0.3 g gallium nitrate and 6.3 g thallous nitrate, dissolved in 70 ml 'distilled water, on 100 g SA5205 catalyst support, described in EXAMPLE-1, by incipient wetness technique, drying the impregnated mass in an air oven at 120°C for 8 h and calcining in air at 550°C for 4 h. The surface area of the catalyst was EXAMPLE-9 A supported catalyst : Zno.o3T10o.53 (20.4 wt%) / SZ5564 was prepared by impregnating a mixture of 0.1 g zinc acetate and 5.0 g thallous acetate, dissolved in 14 ml distilled water, on 20 g fine particles ( >100 mesh ) of SZ5564 catalyst support [obtained from M/s. NORTON Co. U.S.A.. main chemical composition = 94.1 % (ZrO2 + Hf02), 3.5 % CaO, 1.6 % SiO2 and 0.41 % Al3O3; surface area = 0.1m2g "' ; porosity = 45 %] by incipient wetness technique, drying the impregnated mass in an-air oven at 110°C for 10 h and calcining in air at 550°C for 4 h. The surface area of the catalyst was 0.22 m2g~'. EXAMPLE-IQ A supported catalyst : Zn3oGai.oTli.oIno.5034 (11.3 wt%) / SA5205 was prepared by impregnating a mixture of 0.3 moles of zinc nitrate, 0.01 moles of gallium nitrate, 0.01 moles of thallic nitrate and 0.005 moles of indium nitrate, dissolved in 300 ml of distilled water, on 250 g SA5205 catalyst support, described in EXAMPLE-1, by wet impregnation technique, evaporating on water bath the excess solution while stirring, drying the impregnated mass in an air oven at 120aC for 10 h and calcining in air at 500°C for 4 h. The surface area of the catalyst was 0.3 m:g" 1. In the wet impregnation technique, a more volume of impregnation solution than that required for completely wetting the solid to be impregnated is used and the excess of the solution is evaporated while stirring until there is no free solution is left in the impregnation mixture. The main advantages of the supported catalysts of this invention over the prior art catalysts useful for the Friedel-Crafts reactions are as follows: 1. The supported catalysts of this invention has a number of advantages over the earlier homogeneous catalysts used for the Friedel-Crafts reactions, as follows: According to this invention i) the catalyst used for the Friedel-Crafts reaction is heterogeneous solid catalyst and hence it can be separated from the reaction products simply by filtration, and moreover since the catalysts are supported ones, their filtration is easier, ii) the separated catalysts can be reused in the process for a number of times, and iii) also the catalysts are non corrosive, therefore most of the serious problems associated with homogeneous catalyst used in the earlier homogeneous catalysed Friedel-Crafts reactions are overcome by the supported solid catalysts of this invention. 2. The catalysts of this invention have also number of advantages over the prior art solid catalysts used for the Friedel-Crafts reactions, as follows: i) The activity of the catalysts of this invention in the Friedel-Crafts reactions is higher, ii) The catalysts of the present invention can be used for the Friedel-Crafts reactions involving reactants of any molecular size i.e. for both small and big reactant molucules. iii) By using the catalysts of this invention, the Friedel-Crafts reactions can be carried out at mild reaction conditions even though when the aromatic compound does not contain any aromatic nucleus activating group or electron donating group, for example when aromatic compound is benzene, or also when the aromatic compound contains electron withdrawing group, such as halide, which has highly deactivating effect on the aromatic nucleus for the alkylation, aralkylation, acylation or aroylation reaction. We claim; 1. A process for the preparation of supported solid catalysts, useful for the Friedel-Crafts reactions, wherein said catalysts are represented by formula : AaMZ,(c) / S wherein, A is selected from chemical elements Ga, Al. B, Zn, Fe, Sn, Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In, TI or a mixture thereof: Z is selected from chemical elements O, Cl, Br or I; S is porous catalyst support or carrier; a is A/M mole ratio in the range of about 0.001 to about 100; b is number of atoms of Z needed to fuif 1 the valence requirement of the metallic elements AaM present in the supported catalyst; c is weight percentage loading of AaMZb deposited on said catalyst support or carrier (S) in the range of about 0.5 to about 50; wherein said process comprises : (i) depositing on said catalyst support mixed metal halides represented by formula : A=MDj, wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn, Ti, Th. Zr or a *• mixture of two or more thereof; M is selected from chemical elements In, TI or a mixture I thereof; D is chemical group selected from halogen Cl, Br or I or a mixture thereof: a is A/M mole ratio in the range of about 0.001 to about 100; and d is number of atoms of D needed to fulfil the valence requirement of the metallic elements AaM; from non-aqueous moisture-free solvent, in which said mixed metai halides are dissolved, by known catalyst impregnating techniques, such that the weight percent loading of said mixed racial h2..ides on said catalyst support is in the range of about 0.5 \vt% to about 50 wt%; or depositing on said catalyst support mixed metal compounds represented by formula : AaMEe, wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn, Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In. Tl or a mixture thereof; E is chemical group selected from 0, NO3, OH, halo, alkoxide's or CnHan+iCOO, wherein n is in the range of 0 to 15; a is A/M mole ratio in the range of about 0.001 to about 100; e is number of groups of E needed to fulfil the valence requirement of the metallic elements AaM; by known catalyst impregnation, coating or co-precipitation techniques, such that the weight percent loading of said catalyst support is in the range of about 0.5 wt% to about 50 wt%, (ii) heating the catalyst mass obtained from the step-i to dryness at a temperature of about 25°C to about 250°C under vacuum or in presence of air or inert gas, (iii) calcining the dried mass obtained from step-ii at a temperature of about 100°C to about 700°C under vacuum or in presence of air or inert gas for about 0.1 h to about 100 h to gel . the catalyst. 2. A process as claimed in claim 1, wherein Sis selected from micro- and/or meso porous zeolites and zeolite-like materials, synthetic and natural clays, silica gel, alumina and meso and or macroporous catalyst carriers containing SiO;, A1203, SiC, ZrO:, HfO2 or a mixture thereof. 3. A process as claimed in claims 1 to 2, wherein c is from 2 wt% to 20 wt%. 4. A process as claimed in claims 1 to 3, wherein the period of catalyst calcination is from 0.25 h to 25 h. 5. A process as claimed in claims 1 to 4, wherein A is chemical element Ga, Fe, Zn or a mixture thereof. 6. A process as claimed in claims 1 to 5, wherein Z is chemical element O or Cl. 7. A process for the preparation of supported solid catalysts useful for Friedel-Crafts reactions, substantially as herein described with reference to the examples.

Full Text

This invention relates to a process for the preparation of supported catalysts useful for the Friedel-Crafts reactions. This invention particularly relates to a process for the preparation of supported solid catalysts, comprising of mixed metal oxides or halides deposited on porous catalyst carriers or supports, useful for the heterogeneously or solid catalyzed Friedel-Crafts reactions.
The process of this invention could be used for the preparation of solid catalysts useful in the Friedel-Crafts reactions.
A number of homogeneous and heterogeneous acidic catalysts useful for the Friedei-Crafts reactions, for example alkylation, polyalkylation, aralkylation, acylation, aroylation and the like, are known in the prior art. Homogeneous Catalysts for Friedel-Crafts Reactions
The acylation and benzoylation of aromatic compounds and related Friedel-Crafts type reactions using homogeneous lewis acid catalysts are well-known in the prior an [ref. G. A. Olah. in Friedel-Crafts and related reactions: vol. Ill, Acylation and related reactions, Wiley-Interscience PubL New York, 1964]
A use of CuCh as a homogeneous catalyst in the benzylation of benzene or substitute: be-zenes b> benzyl chloride is disclosed in two US patens: TJ.S. 3,678,122(1972) and L'.S 3,679,760(1972). A French patent, Fr. Demande 2.144.578(1973), disclosed nenzylation of p substituted ohenols by benzyl hali.l.s in .he oresence of homogeneous Zr.Ch catalyst. - •. USSR patent, L.S.S.R. 394,353(197 ), disclosed a use of SnSCu or SnC '•-, as :., :iogeneous catalyst for the benzylation with benzyl chloride of m-dimethoxy benzene. A Japanese patent. Japan Kokai 7399,154(1973), disclosed preparation of dibenzyl benzene derivatives by benzylation of benzene or substituted benzenes using AlCl3, FeCb and 98% IbSO4. A use of H2SO4 or H3PO4 and optionally 4-CH3CoH4SO3H, ZnCl2, BF3, etc. in the preparation of c-
benzyltoluenes by the reaction of a o-chloromethyltoluene with a benzene derivative is disclosed in a German patent, Ger. Offen 2,456,747 (1976). A use of phosphoric acid and optionally H2S04 or a Friedel-Crafts type metal halide in the benzylation of benzene with benzylether is disclosed in a US Patent, U.S. 4,049,733 (1977).
A German patent, Ger.offen 2,451,037 (1976), disclosed the use of HF as a catalyst for the benzoylation of aromatic compounds.
A French patent, Fr. Demande FR 2,496,097 (1982) disclosed the acylation of benzene by phthaleic anhydride using HF-BFa mixture.
More recently, an European Patent, Eur.Pat.Appl.EP 538,704 (1993), disclosed a process for the preparation of p-substituted o-benzylphenols by treating phenols. p-R GjH4OH (R = halo, alkyl, OH, alkoxy, alkylmercapto, aryl, aryloxy or arylmercapto), with ArCH:X (Ar = corresponding aryl nucleus; X = halo, arylcarboxy, phenylsulfatoxy, hydroxy. alkoxy etc.) in a continuously functioning distillation apparatus in the presence of dissolved acid catalyst.
The main disadvantages of the use of homogeneous acid catalyst for the Friedel-Crafts processes are as follows:
1) The separation and recovery of the dissolved acid catalysts from the hqu: : reaction
mixture is diffici.it.
2) The disposal of the used acid catalys' • creates environmental pollution.
3) The homogeneous acid ca ~:;. ts also lose several other problems such as high toxicity,
corrosion, spent acid disposal and use of more than the stoichiometric amount.
Heterogeneous Catalysts for Friedel-Crafts Reactions
A German patent, Ger.Offen 2,547,030 (1977), disclosed the preparation of o-benzyltoluenes by the reaction of o-methylbenzyl halides with substituted benzenes in the presence of Al-silicate. The 2-CH3C6H4CH2Cl was stirred with toluene and Al-silicate (25%Al2O3) at 110°C to give 81% 2-methylbenzyltoluene. According to a Japanese patent. Jpn. Kokai Tokkyo Koho JP 59,186,937 (1984), o-benzylphenol was prepared by the liquid phase reaction of benzyl alcohol with phenol in the presence of y-A^Oa. For example 7.5 g y-AhCh was added to a mixture of 32.5 g benzyl alcohol and 47 g phenol at 190°C under stirring to give a product containing 49.9% o-benzylphenol. A German Patent, Ger. Offen DE 3.700,917 (1988), disclosed the preparation of p-substituted o-benzylphenols by benzylation of p-substituted phenols with benzylalcohol in the presence of Na-Y type zeolite. A mixture of 0.5 mole 4-ClC6H4OH, 0.1 mole C0H5CH2OH and 0.6 g of Na-Y type zeolite was heated at 200°C for 3 hrs to give 25.4 % 2-benzyl-4-chlorophenol.
A French patent, Fr. Demande FR 2,667,063 (1992), disclosed the preparation of 4-substituted benzophenones by aroylation of substituted benzenes by substituted benzoic acid in the presence of HY and HP type zeolites. Accordingly 4-C1 C6H4COOH and PhMe were heated 4 h at 200°C under 2 x 10" Pa in the presence of calcined zeolite HB to give 84.4% 4-(4-ClC6H4CO)C6H4Me.
A recent paper by Vincent et al. (ref. Tetrahedron Lett. 35, 1994, 2601), disclosed that H-ZSM-5 zeolite can catalyze the benzoylation by benzoyl chloride of phenol and anisole but not the benzoylation with benzoyl chloride of benzene , halobenzene and naphthalene, at 120°Cfor5h.
A German patent, Ger. Offen DE 3,836,780 (1990), disclosed the process for the preparation of benzylbenzenes from benzenes and benzyl alcohols in the presence of activated
bleaching earth and a diluent at 90-140°C. According to Japanese patent, Jpn Kokai Tokkyo Koho JP 03,170,442 (1991), benzylbiphenyls are manufactured by benzylating biphenyl and diphenylmethane with > 1 compound from benzyl halides, benzyl alcohol, benzyl ether in the presence of a zeolite or silica-alumina catalyst. An European patent, Eur.Pat. appl. EP 428,081 (1991), disclosed a process of benzylation of alkylbenzenes with benzyl chloride in the presence of H-Y or H-L zeolite catalyst. According to a German patent, Ger. Offen DE 4,038,933 (1992), disclosed a process for benzylation of aromatics using technical carbon catalysts.
Alkylation, aralkylation, acylation or aroylation of aromatic- compound involves electrophilic substitution of H from the aromatic nucleus of the aromatic compound. It is well known in the prior art that the electrophilic substitution is favoured by the presence of electron donating groups, such as OH, alkyl, alkoxy, phenoxy, amine, alkyl amine, SH etc., in the aromatic compound. Whereas the electrophilic substitution is inhibited by the presence of electron withdrawing groups such as halo, nitro. cyano, carboxy, aldehyde, etc., in the aromatic compound, [ref. G.A.Olah, in Friedei-Crafts and related reactions, Wiiey-Interscience Publ., New York, 1963].
Although some imitations of the homogeneous acu a::ryze; processes are overcome in the prior art heterogeneous catalyzed processes descriDcv: above, the aiicyiating. aralkylating. acylating or aroylating activity of the solid catalysts used in the prior an processes are low, particularly for alkylating, aralkylating, acylating or aroyL.ting aromatic compounds containing electron withdrawing groups. Hence there is a great practical need for finding more efficient solid catalyst for the alkylaiing, aralkylating, acylating or aroylating of aromatic compounds. There is also a need for finding highly efficient solid catalyst also for the alkylating, aralkylating, acylating or aroylating of aromatic compounds containing
electron withdrawing groups such as halo, nitro, cyano, carboxy, aldehyde, etc.. This invention is, therefore, made with the following objects so that most of the drawbacks or limitations of the prior art homogeneous and heterogeneous catalyzed processes for the Friedel-Crafts type reactions could be overcome.
1. Accordingly, the main object of this invention is to provide a novel supported catalysts
comprising mixed metal oxides or halides, which have high activity for the Friedel-
Crafts reactions not only when the aromatic ring activating groups (i.e. electron
donating groups such as alkyl, hydroxy, alkoxy, etc) are present in the aromatic ring to
be aralkylated, acylated or aroylated but also when the ring activating group is absent
or when aromatic ring deactivating groups (i.e. electron withdrawing groups such as
halo, nitro, etc) are present in the aromatic ring to be aralkylated, acylated or
aroylated. so that the reaction temperature is low and/or time for completing the
reaction is short.
2. Another important object of this invention is to provide novel solid catalysts for the
heterogeneous Friedel-Crafts reactions, which can be reused repeatedly for the
catalytic reactions.
Accordingly this invention provides a process for the preparation of supported solid catalysts, useful for the Friedel-Crafts reactions, wherein said catalysts are represented by formula
AaMZb(c) / S
wherein, A is selected from chemical elements Ga, Al, B, Zn, Fe. Sn, Ti, Th, Zr or a mixture of rwo or more thereof; M is selected from chemical elements In, Tl or a mixture thereof; Z is selected from chemical elements 0, Cl, Br or I; S is porous catalyst support or carrier: a is
AM mole ratio in the range of about 0.001 to about 100; b is number of atoms of Z needed to
fulfil the valence requirement of the metallic elements AaM present in the supported catalyst; c is weight percentage loading of AaMZb deposited on said catalyst support or carrier (S) in the range of about 0.5 to about 50;
wherein said process comprises :
(i) depositing on said catalyst support mixed metal halides represented by formula : AaMDd,
wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn. Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In, Tl or a mixture thereof; D is chemical group selected from halogen Cl, Br or I or a mixture thereof; a is A/M mole ratio in the range of about 0.001 to about 100; and d is number of atoms of D needed to fulfil the valence requirement of the metallic elements AaM; from non-aqueous moisture-free solvent, in which said mixed metal halides are dissolved, by known catalyst impregnating techniques, such that the weight percent loading of said mixed metal halides on said catalyst support is in the range of about 0.5 wt% to. about 50 wt%; or
depositing on said catalyst support mixed metal compounds represented by formula : AaMEe,
wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn. Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In, Tl or a mixture thereof; E is chemical group selected from O, NCb, OH, halo, alkoxides or CnH2n+iCOO, wherein n is in the range of 0 to 15; a is A/M mole ratio in the range of about 0.001 to about 100; e is number of groups of E needed to fulfil the valence requirement of the metallic elements AaM; by known catalyst impregnation, coating or
co-precipitation techniques, such that the weight percent loading of said catalyst support is in the range of about 0.5 wt% to about 50 wt%,
(ii) heating the catalyst mass obtained from the step-i to dryness at a temperature of about 25°C to about 250°C under vacuum or in presence of air or inert gas,
(iii) calcining the dried mass obtained from step-ii at a temperature of about 100°C to about
700°C under vacuum or in presence of air or inert gas for about 0.1 h to about 100 h. In the process of this invention, the porous catalyst carrier or support, S, is selected from micro- and/or meso porous zeolites and zeolite-like materials, synthetic and natural clays, silica gel, alumina and meso and/or macroporous catalyst carriers containing SiO:, A1:O?, SiC, ZrO:, HfO2 or a mixture thereof, and more preferably, S is selected from mesoporous zeolites such as high silica MCM-41 and the like, silica gel cation exchange clays such as montmorillonite clay and the like, and chemically inert or sintered low surface area macroporous catalyst carriers or supports containing SiO2, AliOj, SiC, ZrO2, HfC>2 or a mixture thereof.
In the process of this invention, a preferred loading of the active catalyst mass (AaMZb, as described above) on the porous catalyst carrier or support (S), c. is from 2 wt% to 20 wt%; the preferred period of catalyst calcination in the step-iii of said catalyst preparation process is from 0.25 h to 25 h: the preferred chemical element A is Ga. Fe. Zn or a mixture thereof; and the preferred chemical element Z is 0 or Cl.
The product obtained from the process of this invention is a novel supported solid catalyst comprising of mixed metal oxides or halides deposited on porous catalyst carriers or supports, useful for the Fridel-Crafts reactions such as alkylation, aralkylation. acylation or aroylation of aromatic compounds in the preparation of fine chemicals.
In the process of this invention, said mixed metal oxides or halides (AaMZt) are responsible for the catalytic activity and the main roles played by the porous catalyst carrier or
support (S) are (i) to disperse the active catalyst components (said metal oxides or halides) uniformly and thereby increasing their surface area, (ii) to avoid sintering of said active catalyst components during the catalyst calcination, (iii) to provide high mechanical strength against crushing and/or abrasion to the catalyst during its use in the reaction and (iv) to ease the filtration of the catalyst from the reaction mixture. The said catalyst without catalyst carrier or support may be used for the Friedel-Crafts reactions but said catalyst with catalyst carrier or support is certainly more preferable.
In the process of this invention, the presence of more than one metallic element in said active catalyst mass (AaMZb) is essential for obtaining a synergetic effect, and thereby increasing the catalytic activity of said catalyst.
In the process of this invention, said mixed metal compounds (AaMEe) are catalyst precursors which are converted to mixed metal oxides directly by thermal decomposition or by hydrolysis or co-precipitation followed by calcination or decomposition at said calcination conditions.
In the process of this invention, the non-aquous solvent used for depositing said mixed metal halides (AaMD;) on said catalyst support may be selected from moisture-free volatile organic solvents such as acetonitrile, methanol, nitromethane, chloroform, and the like.
In the process of this invention, said heating step (step-ii) is essential for drying or removing the solvent from the supported catalyst mass obtained in step-i and said calcining step (step-iii) is essential for decomposing said catalyst precursors to corresponding metal oxide or to disperse said mixed metal halides uniformly on the surface of said catalyst carrier or support.
Zeolites are crystalline aluminosilicates containing well defined channels or pores of uniform diameter. A large number of microporous zeolites, such as X, Y, mordenite, L, beta.
ZSM-5, ZSM-8, ZSM-11, etc., and mesoporous zeolites, such as M41S type material, e.g. MCM-41, are known in the prior-art [ ref. Breck in Zeolite Molecular Sieves, Wiley-Interscience Publ., New York, 1974; Beck and Co-workers. J.Am.Chem.Soc., vol.114, page 10834,year 1992; Nature (London) vol.359, page 710, year 1992]. A number of cation exchange natural and synthetic clays having layered silicate structure are known in the prior art [ref. R. A. Schoonheydt "Clays : From two to three dimensions" in Studies in Surface Science and Catalysis, vol. 58, page 201-238, 1991; and K. Ohtsuka, Chem. Mater., vol. 9, page 2039-2051, year 1997].
In general, micropores have diameter below 1 nm; mesopores have diameter between about 1 nm and about 20 nm; and macropores have diameter above about 20 nm. Said catalyst containing only micropores of this process may be used in the Friedel-Crafts reactions when both the reactants of the reaction have critical size (minimum molecular diameter) less than 0.7 nm. Whereas said catalyst containing meso and/or macropores may be used in the said reactions for reactants having both small and large molecular size.
Said catalyst of this invention activates both the reactants of the Friedel-Crafts reactions and thereby shows high activity in the Friedel-Crafts reactions such as alkylation, aralkylation. acylation and aroylation reactions of aromatic compounds containing not only electron donating group, which activates the aromatic ring, but also in the absence of any electron donating group or even containing electron withdrawing group, which deactivates the aromatic ring.
The present invention reveals that the said supported solid catalysts comprising mixed metal oxides or halides deposited on porous catalyst carrier or support, showing very high activity in the Friedel-Crafts reactions such as alkylation, aralkylation. acylation and aroylation reactions of aromatic compounds without containing any electron donating group
or containing electron donating and/or electron withdrawing groups in their aromatic ring, can be prepared by the catalyst preparation process of this invention. Using these catalysts, the Friedel-Crafts reactions can be carried out at lower temperatures and/or in shorter reaction periods.
By using the catalyst of this invention, a complete conversion of benzyl chloride in the benzylation of benzene to diphenyl methane at 80°C and with catalyst/ benzyl chloride wt./wt. ratio of 0.1 and benzene/benzyl chloride mole ratio of 17.0 can be achieved in a reaction period of 8.0 min.
The present invention is described with respect to the following examples illustrating the process of this invention for the preparation of said supported solid catalysts useful for the Friedel-Crafts reactions. These examples are provided for illustrative purposes only and are not to be construed as limitations on the process of this invention.
The main finding of this invention is that, the said catalysts show high activity in the Friedel-Crafts reactions, such as alkylation, aralkylation, acylation and aroylation reactions not only when the electron donating group, which is aromatic ring activating group, is present in the aromatic ring of the aromatic compound but also when the ring activating group is absent or when the electron withdrawing group, which is aromatic ring deactivating group, is present in the aromatic ring of the aromatic compound, so that the reaction temperature is low and/or the time required for completing the reactions is short.
Other important finding of this invention is that said solid catalyst can be separated easily from the reaction mixture and reused repeatedly in the Friedel-Crafts reactions. Yet another important finding of this invention is that the mechanism of the activation of reactants over said solid catalysts is different from that over the acidic catalysts used in the prior art for the Friedel-Crafts reactions.
EXAMPLE-1
A supported catalyst : Ga2.27TlO3.9 (10 wt%) / SA5205 was prepared by impregnating a mixture of 2.05 g gallium nitrate and 0.94 g thallous nitrate, dissolved in 10 ml distilled water, on 15 g SA5205 catalyst support ( obtained from M/s. NORTON Co. U.S.A.), having main chemical composition : 11.8 % SiO2, 86.1 % A12O3; surface area A supported catalyst : Fen.zTlCls-jb (10 wt%) / Montmorrilonite KIO was prepared by impregnating a mixture of 0.9 g ferric chloride and 0.1 g thallic chloride, dissolved in 18 ml moisture-free acetonitrile, on 10 g Montmorillonite KIO clay (obtained from Aldrich Chemical Co. U.S.A.) by incipient wetness technique, drying the impregnated rtiass under vacuum at 40°C for 20 h and then calcining or heating further in a flow of nitrogen free from oxygen and traces of moisture at 120°C for l0h.
EXAMPLE-3
A supported catalyst : Ga12.6lnCl40.8 (H wt%) / Montmorrilonite KIO was prepared by impregnating a mixture of 0.1 g indium chloride and 1.0 g gallium chloride, dissolved in 17 ml moisture-free methanol, on 10 g Montmorillonite KIO clay (obtained from Aldrich Chemical Co. U.S.A.) by incipient wetness technique, drying the impregnated mass under vacuum at 100°C for 1 h and then calcining or heating further in a flow of pure helium at 150°C for 5 h.
EXAMPLE-4
A supported catalyst: Gaio.oInO16.5. (11.8 wt%) / SA5205 was prepared by impregnating a mixture of 2.8 g gallium nitrate and 0.33 g indium nitrate, dissolved in 7 ml distilled water, on 10 g SA5205 catalyst support, described in EXAMPLE-1, by incipient wetness technique, drying the impregnated mass in an air oven at 100°C for 15 h and calcining in air at 600°C for 2 h. The surface area of the catalyst was 3.9 m2g~'.
EXAMPLE-5
A supported catalyst : Gau.oInO18.0.(2.3 wt%) / MCM-41 was prepared by impregnating a mixture of 2.8 g gallium nitrate and 0.3 g indium nitrate, dissolved in 100 ml distilled water, on 50 g high silica meso-porous zeolite [prepared by the procedure described in the ref. Choudhary et al., Proceeding of Indian Academy of Sciences, (Chemical Sciences) volume 109, page 229 and year 1997], by incipient wetness technique, drying the impregnated mass in an air oven at 100°C for 20 h and calcining in air at 500°C for 4 h. The surface area of the catalyst was 1102 m~g"'. EXAMPLE-6
A supported catalyst: Zno.o3T10o.53 (20.4 wt%) / SA5205 was prepared by impregnating a mixture of 0.3 g zinc nitrate and 5.0 g thallous nitrate, dissolved in 14 ml distilled water, on 20 g SA5205 catalyst support, described in EXAMPLE-1, by incipient wetness technique, drying the impregnated mass in an air oven at 120°C for 8 h and calcining in air at 550°C for 4 h. The surface area of the catalyst was ~ 0.1 m2g~'.
EXAMPLE-7
A supported catalyst: Ga29.0 TlO.44.0 (10.8 wt%) / SiO2 gel was prepared by impregnating a mixture of 14.0 g gallium nitrate and 0.5 g thallous nitrate, dissolved in 50 ml distilled water, on 50 g SiO: gel catalyst support (Fuji Davison, A-type, surface area 720 rn2g"')in powdered form, by
incipient wetness technique, drying the impregnated mass in an air oven at 125°C for 6 h and calcining in air at 600°C for 4 h. The surface area of the catalyst was 325 m2g"'.
EXAMPLE-8
A supported catalyst : Ga0.05TlOo.jg (5.1 wt%) / SA5205 was prepared by impregnating a mixture of 0.3 g gallium nitrate and 6.3 g thallous nitrate, dissolved in 70 ml 'distilled water, on 100 g SA5205 catalyst support, described in EXAMPLE-1, by incipient wetness technique, drying the impregnated mass in an air oven at 120°C for 8 h and calcining in air at 550°C for 4 h. The surface area of the catalyst was EXAMPLE-9
A supported catalyst : Zno.o3T10o.53 (20.4 wt%) / SZ5564 was prepared by impregnating a mixture of 0.1 g zinc acetate and 5.0 g thallous acetate, dissolved in 14 ml distilled water, on 20 g fine particles ( >100 mesh ) of SZ5564 catalyst support [obtained from M/s. NORTON Co. U.S.A.. main chemical composition = 94.1 % (ZrO2 + Hf02), 3.5 % CaO, 1.6 % SiO2 and 0.41 % Al3O3; surface area = 0.1m2g "' ; porosity = 45 %] by incipient wetness technique, drying the impregnated mass in an-air oven at 110°C for 10 h and calcining in air at 550°C for 4 h. The surface area of the catalyst was 0.22 m2g~'. EXAMPLE-IQ
A supported catalyst : Zn3oGai.oTli.oIno.5034 (11.3 wt%) / SA5205 was prepared by impregnating a mixture of 0.3 moles of zinc nitrate, 0.01 moles of gallium nitrate, 0.01 moles of thallic nitrate and 0.005 moles of indium nitrate, dissolved in 300 ml of distilled water, on 250 g SA5205 catalyst support, described in EXAMPLE-1, by wet impregnation technique, evaporating on water bath the excess solution while stirring, drying the impregnated mass in an air oven at 120aC for 10 h and calcining in air at 500°C for 4 h. The surface area of the catalyst was 0.3 m:g"
1. In the wet impregnation technique, a more volume of impregnation solution than that required
for completely wetting the solid to be impregnated is used and the excess of the solution is evaporated while stirring until there is no free solution is left in the impregnation mixture.

The main advantages of the supported catalysts of this invention over the prior art catalysts useful for the Friedel-Crafts reactions are as follows:
1. The supported catalysts of this invention has a number of advantages over the earlier
homogeneous catalysts used for the Friedel-Crafts reactions, as follows:
According to this invention
i) the catalyst used for the Friedel-Crafts reaction is heterogeneous solid catalyst and hence
it can be separated from the reaction products simply by filtration, and moreover since the
catalysts are supported ones, their filtration is easier,
ii) the separated catalysts can be reused in the process for a number of times, and
iii) also the catalysts are non corrosive, therefore most of the serious problems associated
with homogeneous catalyst used in the earlier homogeneous catalysed Friedel-Crafts
reactions are overcome by the supported solid catalysts of this invention.
2. The catalysts of this invention have also number of advantages over the prior art solid
catalysts used for the Friedel-Crafts reactions, as follows:
i) The activity of the catalysts of this invention in the Friedel-Crafts reactions is higher, ii) The catalysts of the present invention can be used for the Friedel-Crafts reactions involving reactants of any molecular size i.e. for both small and big reactant molucules. iii) By using the catalysts of this invention, the Friedel-Crafts reactions can be carried out at mild reaction conditions even though when the aromatic compound does not contain any aromatic nucleus activating group or electron donating group, for example when aromatic compound is benzene, or also when the aromatic compound contains electron withdrawing group, such as halide, which has highly deactivating effect on the aromatic nucleus for the alkylation, aralkylation, acylation or aroylation reaction.

We claim;
1. A process for the preparation of supported solid catalysts, useful for the Friedel-Crafts reactions, wherein said catalysts are represented by formula :
AaMZ,(c) / S
wherein, A is selected from chemical elements Ga, Al. B, Zn, Fe, Sn, Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In, TI or a mixture thereof: Z is selected from chemical elements O, Cl, Br or I; S is porous catalyst support or carrier; a is A/M mole ratio in the range of about 0.001 to about 100; b is number of atoms of Z needed to fuif 1 the valence requirement of the metallic elements AaM present in the supported catalyst; c is weight percentage loading of AaMZb deposited on said catalyst support or carrier (S) in the range of about 0.5 to about 50;
wherein said process comprises :
(i) depositing on said catalyst support mixed metal halides represented by formula : A=MDj, wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn, Ti, Th. Zr or a
*•
mixture of two or more thereof; M is selected from chemical elements In, TI or a mixture
I
thereof; D is chemical group selected from halogen Cl, Br or I or a mixture thereof: a is A/M mole ratio in the range of about 0.001 to about 100; and d is number of atoms of D needed to fulfil the valence requirement of the metallic elements AaM; from non-aqueous moisture-free solvent, in which said mixed metai halides are dissolved, by known catalyst impregnating techniques, such that the weight percent loading of said mixed racial h2..ides on said catalyst support is in the range of about 0.5 \vt% to about 50 wt%; or
depositing on said catalyst support mixed metal compounds represented by formula : AaMEe,
wherein A is selected from chemical elements Ga, Al, B, Zn, Fe, Sn, Ti, Th, Zr or a mixture of two or more thereof; M is selected from chemical elements In. Tl or a mixture thereof; E is chemical group selected from 0, NO3, OH, halo, alkoxide's or CnHan+iCOO, wherein n is in the range of 0 to 15; a is A/M mole ratio in the range of about 0.001 to about 100; e is number of groups of E needed to fulfil the valence requirement of the metallic elements AaM; by known catalyst impregnation, coating or co-precipitation techniques, such that the weight percent loading of said catalyst support is in the range of about 0.5 wt% to about 50 wt%,
(ii) heating the catalyst mass obtained from the step-i to dryness at a temperature of about 25°C to about 250°C under vacuum or in presence of air or inert gas,
(iii) calcining the dried mass obtained from step-ii at a temperature of about 100°C to about 700°C under vacuum or in presence of air or inert gas for about 0.1 h to about 100 h to gel . the catalyst.
2. A process as claimed in claim 1, wherein Sis selected from micro- and/or meso porous zeolites
and zeolite-like materials, synthetic and natural clays, silica gel, alumina and meso and or
macroporous catalyst carriers containing SiO;, A1203, SiC, ZrO:, HfO2 or a mixture thereof.
3. A process as claimed in claims 1 to 2, wherein c is from 2 wt% to 20 wt%.
4. A process as claimed in claims 1 to 3, wherein the period of catalyst calcination is from 0.25 h
to 25 h.
5. A process as claimed in claims 1 to 4, wherein A is chemical element Ga, Fe, Zn or a mixture
thereof.
6. A process as claimed in claims 1 to 5, wherein Z is chemical element O or Cl.
7. A process for the preparation of supported solid catalysts useful for Friedel-Crafts reactions,
substantially as herein described with reference to the examples.

Documents:

2388-del-1998-abstract.pdf

2388-del-1998-claims.pdf

2388-del-1998-correspondence-others.pdf

2388-del-1998-correspondence-po.pdf

2388-del-1998-description (complete).pdf

2388-del-1998-form-1.pdf

2388-del-1998-form-19.pdf

2388-del-1998-form-2.pdf

2388-del-1998-form-3.pdf

2388-del-1998-petition-138.pdf

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Patent Number

215581

Indian Patent Application Number

2388/DEL/1998

PG Journal Number

11/2008

Publication Date

14-Mar-2008

Grant Date

27-Feb-2008

Date of Filing

13-Aug-1998

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG NEW DELHI-110001 INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	DR. VASANT RAMCHANDRA CHOUDHARY	NATIONAL CHEMICAL LABORATORY, PUNE-8.
2	MS. SUMAN KUMAR JANA	NATIONAL CHEMICAL LABORATORY, PUNE-8.
3	MR. B-PHANI KIRAN	NATIONAL CHEMICAL LABORATORY, PUNE-8.

PCT International Classification Number

C07C

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA