MXPA99007212A - Hydroperoxide decomposition process - Google Patents

Abstract

An improved process for decomposing alkyl or aromatic hydroperoxides to form a decomposition reaction mixture containing the corresponding alcohol and ketone. The improvement relates to decomposing the hydroperoxide by contacting the hydroperoxide with a catalytic amount of a heterogenous catalyst of Au, Ag, Cu or a sol-gel compound containing particular combinations of Cr, Co, Zr, Ta, Si, Mg, Nb, Al and Ti wherein certain of those metals have been combined with an oxide, such as an inorganic matrix of hydroxides or oxides, or combinations thereof. The catalysts may also optionally be supported on a suitable support member.

Description

DECOMPOSITION PROCESS OF HYDROPEROXIDES Field of the Invention The invention relates in general to an improved catalytic process for the decomposition of alkyl or aromatic hydroperoxides to form a mixture containing the corresponding alcohol and ketone. In particular, the invention relates to the decomposition of a hydroperoxide by contacting it with a catalytic amount of a heterogeneous catalyst of Au, Ag, Cu or a sol-gel compound containing particular combinations of Cr, Co, Zr, Ta, Yes, Ti, Nb, Al and Mg, where certain of these metals have been combined with an oxide.

Background of the Invention Industrial processes for the production of mixtures of cyclohexanol and cyclohexanone from cyclohexane are commonly of considerable commercial significance and are well described in the patent literature. In accordance with typical industrial practice, the cyclohexane is oxidized to form a mixture of Ref.30838 reaction containing cyclohexyl hydroperoxide (CHHP). The resulting CHHP is decomposed, optionally in the presence of a catalyst, to form a reaction mixture containing cyclohexanol and cyclohexanone. In industry, such a mixture is known as a K / A mixture (ketone / alcohol), and can easily be oxidized to produce adipic acid, which is an important reagent in the processes for preparing certain condensation polymers, especially polyamides. Due to the large volumes of adipic acid consumed in these and other processes, improvements in the processes for producing adipic acid and its precursors can be used to provide cost-beneficial benefits. Druliner et al., In U.S. Pat. No. 4,326,084, discloses an improved catalytic process for oxidizing cyclohexane to form a mixture of the reaction containing CHHP, and to subsequently decompose the resulting CHHP to form a mixture containing K and A. The improvement involves the use of certain complexes of transition metal of the 1,3-bis (2-pyridylimino) isoindolines as catalysts for the oxidation of cyclohexane and for the decomposition of CHHP. According to this patent, these catalysts demonstrate a longer catalyst life, a conversion of higher CHHP to K and A, an operation at lower temperatures (80-16C ° C), and a reduced formation of metal-containing solids. insoluble, in relation to the results obtained with certain fatty acid salts of cobalt (II), for example, cobalt 2-ethylhexanoate. Druliner et al., In U.S. Pat. No. 4,503,257, describes another improved catalytic process for oxidizing cyclohexane to form a reaction mixture containing CHHP, and for the subsequent decomposition of the resulting CHHP to form a mixture containing K and A. This improvement involves the use of Co304, Mn02, or Fe30 applied to a solid support suitable as catalysts for the oxidation of cyclohexane and the decomposition of CHHP at a temperature from about 80 ° C to about 130 ° C, in the presence of molecular oxygen. Sanderson et al., In U.S. Pat. No. 5,414,163, describes a process for preparing t-butyl alcohol from t-butyl hydroperoxide in the liquid phase on catalytically effective amounts of titania, zirconia, or mixtures thereof. Sanderson et al., In U.S. Pat. Nos. 5,414,141, 5,399,794 and 5,401,889, describes a process for preparing t-butyl alcohol from t-butyl hydroperoxide in the liquid phase on catalytically effective amounts of the paladic with gold as a dispersion agent supported on alumina. Druliner et al., In the provisional U.S. 60 / 025,368 filed September 3, 1996 (now PCT patent US97 / 15332 filed on September 2, 1997), describes the decomposition of a hydroperoxide by contacting it with a catalytic amount of a heterogeneous catalyst of hydroxides or oxides of Zr., Nb, Hf and Ti. Preferably, the catalyst is supported on Si02, A1203, carbon or Ti02. Further improvements and options are necessary for the decomposition of the hydroperoxide to K / A mixtures to overcome the deficiencies inherent in the prior art. Other objects and advantages of the present invention will become apparent to those skilled in the art with reference to the detailed description which will be given hereinafter.

Brief Description of the Invention In accordance with the present invention, an improved process is provided in which a hydroperoxide is decomposed to form a decomposition reaction mixture containing a corresponding alcohol and the ketone. The improvement comprises decomposing the hydroperoxide by contacting the hydroperoxide with a catalytic amount of a heterogeneous catalyst selected from the group consisting of (1) Au (gold), (2) Ag (silver), (3) Cu (copper) and (4) sol-gel compounds comprised of (a) one or more elements selected from a first group consisting of Cr, Co and Ti and (b) one or more elements selected from a second group consisting of Zr, Ta, Nb, Si, Al, Mg and Ti, where the elements selected from (b) are combined with an oxide and where the elements of the first group can not be the same as the elements of the second group. Preferably, an inorganic matrix of the oxides or hydroxides, or combinations thereof, is used as the oxide. In addition, the catalysts are optionally supported on a suitable support element, such as Si02, A1203, carbon, zirconia, MgO or Ti02.

Detailed Description of the Preferred Modalities The present invention provides an improved process for carrying out a decomposition weight of the hydroperoxide in an industrial process in which an alkyl or aromatic compound is oxidized to form a mixture of the corresponding alcohol and the ketone. In particular, the cyclohexane can be oxidized to form a mixture containing cyclohexanol (A) and cyclohexanone (K). The industrial process involves a few steps: first, the cyclohexane is oxidized, forming a reaction mixture containing CHHP; second, the CHHP is decomposed, forming a mixture containing K and A. As previously mentioned, the processes for the oxidation of cyclohexane are well known in the literature and are available to those skilled in the art. The advantages of the present heterogeneous catalytic process, in relation to the processes employing homogeneous metal catalysts, such as metal salts or metal / ligand mixtures, include longer catalyst life, improved yields of useful products, and absence of soluble metal compounds. The improved process may also be useful for the decomposition of other alkane or aromatic hydroperoxides, for example, t-butyl hydroperoxide, cyclododecyl hydroperoxide and eumeno nidroperóxido. The CHHP decomposition processes can be carried out under a wide variety of conditions and in a wide variety of solvents, including cydohexane itself. Since CHHP is typically produced industrially as a cyclohexane solution from the catalytic oxidation of cyclohexane, a convenient and preferred solvent for the decomposition process of the invention is cyclohexane. Such a mixture may be used as received from the first step of the cyclohexane oxidation process or after some of the constituents have been removed by known processes such as distillation or aqueous extraction to remove the carboxylic acids and other impurities. The preferred concentration of CHHP in the feed mixture of CHHP decomposition may vary from about 0.5% by weight to 100% (ie, pure). In the industrially practical route, the preferred range is from about 0.5% to about 3% by weight. Suitable reaction temperatures for the process of the invention range from about 80 ° C to about 170 ° C. Temperatures from about 110 ° C to about 130 ° C are typically preferred. The pressures of the reaction may preferably vary approximately from a pressure of 69 kPa to about 2760 kPa (10-400 psi), and pressures from about 2 ^ 6 kPa to about 1380 kPa (40-200 psi) are more preferred . The reaction times vary inversely with respect to the reaction temperature, and typically vary from about 2 to about 30 minutes. As previously noted, the heterogeneous catalysts of the invention include Au, Ag, Cu (including, but not limited to, Au sol, Ag and Cu compounds) and certain sol-gel compounds other than Au / Ag / Cu, preferably applied to suitable solid supports. The process of the invention can also be carried out using the Au, Ag or Cu in the presence of other metals (for example, Pd). The percentage of the metal with respect to the support can vary from about 0.01 to about 50 weight percent, and preferably is from about 0.1 to about 10 weight percent. Suitably, the currently preferred supports include SiO2 (silica), A1203 (alumina), C (carbon), TiO2 (titania), MgO (magnesia) or ZrO2 (zirconia). Zirconia is a particularly preferred support, and the Au supported on zirconia is a particularly preferred catalyst of the invention.

Some of the heterogeneous catalysts of the invention can be obtained either prepared from the manufacturers, or they can be prepared from suitable starting materials using methods known in the art. These methods may include soi-gel techniques as described in more detail below to prepare both Au / Ag / Cu sol-gel compounds and other sol-gel compounds other than Au / Ag / Cu. The supported gold catalysts can be prepared by any standard procedure that is known to give the gold well dispersed, such as by evaporative techniques or coatings of colloidal dispersions. In particular, gold of ultrafine particle size is preferred. Such small particulate gold (often smaller than 10 nm) can be prepared according to Haruta, M., "Size-and Support-Dependency in the Catalysis of Gold", Catalysis Today 36 (1997) 153-166 and Tsubota et al. ., Preparation of Catalysts V, pp. 695-704 (1991). Such gold preparations produce samples that are purple-pink in place of the typical bronze color associated with gold and lead to highly dispersed gold catalysts when placed on a suitable support element. These highly dispersed gold particles are from about 3 nm to about 15 nm in diameter. The solid support of the catalyst, which includes Si02, A1203, carbon, MgO, zirconia, or Ti02, can be amorphous or crystalline, or a mixture of amorphous and crystalline forms. The selection of an optimum average particle size for the catalyst supports will depend on process parameters such as residence time in the reactor and the desired reactor flow rates. In general, the average particle size will vary from about 0.005 mm to about 5 mm. Catalysts having a surface area greater than 10 m2 / g are preferred since the increased surface area of the catalyst has a direct correlation with the increased decomposition rates in batch experiments. Brackets that have much larger surface areas can also be employed, but the inherent fragility of catalysts with a large surface area, and the problems that arise during the maintenance of an acceptable particle size distribution, will establish a practical upper limit on the surface area of catalyst support. Other catalysts useful in the present invention are comprised of certain metals (including metal ions) combined with an oxide, such as an inorganic matrix of oxides or hydroxides, or combinations thereof. The metals include Cr, Co, Zr, Ta, Nb, Al, Si, Ti and Mg, present in combinations as described above. The mole percentage of the metals in the matrix can vary, as can the number of different metals and their relative proportions. They may also have a variable hydroxide content, which may depend on the calcination temperature, if it is effected, and other parameters. The transition metals of Co and Cr may be present as inorganic salts while Zr, Ta, Nb, Si, Al, Ti and Mg may be present as an oxide, a hydroxide, or combinations thereof. (Note that for simplification the corresponding anions are not shown for these cations in the formulas identified here). Typical preparations involve the sol-gel chemistry where the metals are co-hydrolyzed and / or trapped in the center of an inorganic matrix. A better dispersion and uniformity of the metal can be obtained compared to that which can be achieved normally using more conventional synthetic methods. The inorganic matrix can optionally be supported on an appropriate support element, such as Si02, A1203, Zr02, carbon, MgO, or Ti02. The preferred catalysts of this type are those containing Cr and / or Co. A "sol-gel technique" is a process wherein a free flowing fluid solution "sol", it is prepared first by dissolving suitable precursor materials such as colloids, alkoxides or metal salts in a solvent. The "sol" is then dosed with a reagent to initiate the reactive polymerization of the precursor. A typical example is tetraethoxyorthosilicate (TEOS) dissolved in ethanol. Water, with an acid or trace base as the catalyst to initiate hydrolysis, is added. When polymerization and crosslinking proceed, the freely flowing "sol" increases in viscosity and may eventually harden to a rigid "gel". The "gel" consists of a reticulated network of the desired material which encapsulates the original solvent within its open porous structure. The "gel" can then be dried, typically either by simple heating in a flow of dry air to produce a xerogel or the trapped solvent can be removed by displacement with a supercritical fluid such as liquid C02 to produce an airgel. These aerogels and xerogels can be optionally calcined at elevated temperatures (>; 200 ° C) which leads to products which typically have very porous structures and concomitantly large surface areas. In the practice of the invention, the catalysts can be contacted with the CHHP by the formulation in a catalyst bed, which is positioned to provide intimate contact between the catalysts and the reactants. Alternatively, the catalysts can be converted to a suspension using techniques known in the art. The process of the invention is suitable for continuous or batch CHHP decomposition processes. These processes can be carried out under a wide variety of conditions. The addition of air or a mixture of air and inert gases to the decomposition mixtures of CHHP provides larger conversions of the process reagents to K and A, since some of the cyclohexane is directly oxidized to K and A, in addition to K and To which are formed by decomposition of CHHP. This ancient process is known as the "cyclohexane share", and is described in detail in Druliner et al., U.S. Pat. No. 4,326,084, the complete content of which is incorporated herein for reference.

The process of the present invention is further illustrated by the following non-limiting examples. In these examples, all temperatures are in degrees centigrade and all percentages are by weight unless otherwise indicated.

EXPERIMENTS Experiment 1 ~ 1-4% Au on Coal g of 20-35 mesh (0.5-0.85 mm) mineral carbon (EM Science, Cherry Hill, NJ) is calcined in flowing helium (100 ml / min) at 400 ° C for 1 hour. This material is then converted into a suspension in a solution of 0.1 g of gold trichloride in 10 ml of water containing 1 ml of concentrated HCl. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined in nitrogen that is flowing (100 ml / min) at 400 ° C for 1 hour, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Ex ~ erimento 2 ~ 1.4% Au on Silica g of mesh silica gel + 8 with a surface area of 300 m2 / g and a pore volume of 1 cc / g (Alfa Aesar, Ward Hill, MA) are calcined in helium that is flowing (100 ml / min. ) at 400 ° C for 1 hour. This material is then converted into a suspension in a solution of 0.1 g of gold trichloride in 10 ml of water containing 1 ml of concentrated HCl. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined in flowing nitrogen (100 ml / min) at 400 ° C for 1 hour, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Experiment 3 ~ 14% Au on Silica g of silica gel of < 2 microns with a surface area of 450 m2 / g and a pore volume of 1.6 cc / g (Alfa Aesar, Ward Hill, MA) are calcined in helium that is flowing (100 ml / min) at 400 ° C for 1 hour . This material is then converted into a suspension in a solution of 1.0 g of gold trichloride in 100 ml of water containing 1 ml of concentrated HCl. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined on nitrogen that is flowing (100 ml / min) at 400 ° C for 1 hour, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Experiment 4 - Plane Silicon Control g of silica gel mesh + 8 with a surface area of 300 m2 / g and a pore volume of 1 cc / g (Alfa Aesar, Ward Hill, MA) are calcined in helium that is flowing (100 ml / min. ) at 400 ° C for 1 hour. This material is then converted into a suspension in a 10 ml solution of water containing 1 ml of concentrated HCl. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined in flowing nitrogen (100 ml / min) at 400 ° C for 1 hour, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Experiment 5 ~ 1.4% Au on a-Alumina g of 6-12 mesh a-alumina spheres (Calsicat, Erie, PA) are converted into a suspension in a solution of 0.1 g of gold trichloride in 10 ml of water containing 1 ml of concentrated HCl. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined in nitrogen that is flowing (100 ml / min) at 400 ° C for 1 hour, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Experiment 6 ~ 13% Ag on Silica g of silica gel mesh + 8 with a surface area of 300 m2 / g and a pore volume of 1 cc / g (Alfa Aesar, Ward Hill, MA) are calcined in helium which is flowing (100 ml / min) at 400 ° C for 1 hour. This material is then converted into a suspension in a solution of 0.1 g of silver nitrate in 10 ml of water containing 1 ml of concentrated HN03. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined in nitrogen that is flowing (100 ml / min) at 400 ° C for 1 hour, cooled to 200 ° C and calcined another hour in hydrogen that is flowing (100 ml / min) and then stored in a covered vial, hermetically for testing as a decomposition catalyst of CHHP.

Experiment 7 ~ 4.5% Cu on Silica g of silica gel mesh + 8 with a surface area of 300 m2 / g and a pore volume of 1 cc / g (Alfa Aesar, Ward Hill, MA) are calcined in helium that is flowing (100 ml / min. ) at 400 ° C for 1 hour. This material is then converted into a suspension in a solution of 1.0 g of copper nitrate in 10 ml of water containing 1 ml of concentrated HN03. The suspension is stirred for 15 minutes at room temperature and then evaporated to dryness on a rotary evaporator. The recovered solid is calcined in flowing nitrogen (100 ml / min) at 400 ° C for 1 hour, cooled to 200 ° C and calcined another hour in hydrogen that is flowing (100 ml / min) and then Store in a sealed vial for testing as a CHHP decomposition catalyst.

Unlike Experiments i-Experiments 8-13 were carried out according to the general gold deposition technique of Tsubota et al., Preparation of Catalysts V, pp. 695-704 (1991) to produce ultrafine gold particles.These supported catalysts were purple / pink compared to the supported bronze / gold (higher charges) or gray / brown supported catalysts (lower charges) of Experiments 1-7 .

Experiment 8 ~ 1% Gold on MgO g of powdered 200 mesh MgO (Alfa Aesar, Ward Hill, MA) are converted into a suspension in a solution of 0.2 g of gold trichloride in 50 ml of water containing 1 ml of concentrated HCl. The pH of the suspension is adjusted to 9.6 with sodium carbonate solution and then 0.69 g of sodium citrate are added. After stirring for 2 hours at room temperature the solid is recovered by filtration and washed well with distilled water. The recovered solid is calcined in air that is flowing (100 ml / min) at 250 ° C for 5 hours, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Example 9 ~ 1% Au on? -Aluminium g of the powdered 60 mesh α-alumina (Alfa Aesar, Ward Hill, MA) are converted into a suspension in a solution of 0.2 g of gold trichloride in 50 ml of water containing 1 ml of concentrated HCl. The pH of the suspension is adjusted to 9.6 with a sodium carbonate solution and then 0.69 g of sodium citrate are added. After stirring for 2 hours at room temperature the solid is recovered by filtration and washed well with distilled water. The recovered solid is calcined in air that is flowing (100 ml / min) at 250 ° C for 5 hours, cooled and then stored in a sealed vial to test a CHHP decomposition catalyst. The resulting catalyst was purple / pink in color and had a gold particle size of 8 nm as determined by x-ray diffraction (XRD).

Experiment 10 ~ 1% Au on Silica g of silica granules + 8 mesh (Alpha Aesar, Ward Hill, MA) are then converted into a suspension in a solution of 0.2"g of gold trichloride in 50 ml of water containing 1 ml of concentrated HCl.The pH of the suspension is adjusted to 9.6 with a solution of Sodium carbonate and then add 0.69 g sodium citrate After stirring for 2 hours at room temperature the solid is recovered by filtration and washed well with distilled water.The recovered solid is calcined in flowing nitrogen (100 ml / min) at 250 ° C for 5 hours, cooled and then stored in a vial-hermetically sealed for the test as a CHHP decomposition catalyst.

Experiment 11 ~ 1% of Au on Titania • g of pulverized 325 mesh titania (Alfa Aesar, Ward Hill, MA) are then converted into a suspension in a solution of 0.2 g of gold trichloride in 50 ml of water containing 1 ml of concentrated HCl. The pH of the suspension is adjusted to 7.0 with a sodium carbonate solution and then 1.5 g of sodium citrate are added. After stirring for 2 hours at room temperature the solid is recovered by filtration and washed well with distilled water. The recovered solid is calcined in air that is flowing (100 ml / min) at 400 ° C for 5 hours, cooled and then stored in a sealed vial for the test as a CHHP decomposition catalyst.

Experiment 12 ~ 1% Au on Zirconia g of 325 mesh zirconia (Calsicat # 96F-88A, Erie, PA) are converted into a suspension in a solution of 0.2 g of gold chloride in 50 ml of water and 1 drop of concentrated HCl. The suspension is gently agitated when the pH is adjusted to 9.6 with 0.1M sodium carbonate solution. The suspension is stirred gently while 0.69 g of solid sodium citrate are added slowly and then stirred for an additional 2 hours. After it is filtered and washed well with distilled water, the solid is calcined in air that is flowing for 5 hours at 250 ° C.

Experiment 13 ~ 1% Au and 0.1% Pd on Alumina g of α-alumina of 60 mesh are converted into a suspension in a solution of 0.2 g of gold and 0.02 g of tetraamine palladium chloride in 50 ml of water and one drop of concentrated HCl. The suspension is gently shaken when the pH is adjusted to 9.6 with a 0.1M sodium carbonate solution. The suspension is gently stirred again while slowly adding 0.69 g of solid sodium citrate and then stirring for an additional 2 hours. After it is filtered and washed well with distilled water, the solid is calcined in air that is flowing for 5 hours at 250 ° C.

Experiment 14 CrZrO Crp.os (ZrO2-x (OH) 2x) 0.95 218 ml of ethanol (Quantum Chemical, Newark, NJ, scrupulously dehydrated) are combined with 93.4 g of zirconium n-propoxide (70% by weight in n-propanol, Alpha 22989, Ward Hill, MA) in a drying box. N2 of inert atmosphere. 5.24 g of chromium (III) acetylacetonate (Aldrich, 20.223-2, Ward Hill MA) are dissolved in 218 ml of ethanol and added to this solution. In a separate vessel, 218 ml of ethanol are mixed with 20.5 ml of water and 2.45 ml of glacial acetic acid (JT Baker, 6903-05, Phillipsburg, NJ) and 1.91 ml of 70% by weight nitric acid (EM Sciences, Gibbstown NJ). The aqueous solution is added, by dripping, to the solution of zirconium alkoxide. The experiment was carried out in a resin pot under a layer of nitrogen flowing during the addition of the aqueous solution. During the hydrolysis, and prior to the observation of a gel point, some opacity and possible formation of white particles in the zirconium alkoxide solution is noted. The opaque gel material is allowed to stand at room temperature for at least 24 hours. The material is dried at 120 ° C in air at 1 atmosphere prior to use. For some experiments, the material was pressed at 1,407.4 kg / cm2 (20,000 psi) on small discs and granulated to sift through mesh screens -10, +20.

Experiment 15 CrTaO Cro.?5(Ta?2.5-x(OH)2?)?.95 350 ml of ethanol (Quantum Chemical, Newark, NJ, scrupulously dehydrated) are combined with 115.8 g of tantalum ethoxide (Ta (0Et) 5, Aldrich, 33, 91103, Milwaukee, WI) in an atmosphere N2 drying box inert. 5.24 g of chromium (III) acetylacetonate (Aldrich, 20.223-2, Ward Hill MA) are dissolved in 350 ml of ethanol added to the aroxide solution. In a separate vessel, 350 ml of ethanol are mixed with 25.7 ml of water and 3.06 ml of glacial acetic acid (JT Baker, 6903-05, Phillipsburg, NJ) and 2.39 ml of 70% by weight nitric acid (EM Sciences, Gibbstown NJ).

The aqueous solution is added, dropwise, to the tantalum alkoxide solution containing soluble chromium acetylacetonate. The material was contained in a resin pot and placed under a layer of nitrogen that is flowing during this addition. Following the hydrolysis, a dark purple, ciaro gel forms. A clear gel spot was observed after about seven days at room temperature under flowing nitrogen. The material is dried at 120 ° C in air at 1 atmosphere prior to use. For some experiments, the material was pressed at 1,407.4 kg / cm2 (20,000 psi) on small discs and granulated to be sieved through -10, +20 sieves.

Experiment 16 CrTiO Crp.2 (TÍ02 -? (OH) 2x)? 8 13. 85 ml of the 60% by volume solution in ethanol containing titanium n-butoxide [Aldrich, 24-411-2] in ethanol are added to 50.08 ml of ethanol under an atmosphere of inert nitrogen. 6.06 ml of a separate 1.5 molar aqueous solution (metal content) of 1.5 molar chromium hydroxide acetate [Al rich, 31,810-8] is slowly added to the alcohol solution, with gentle swirling, to form the green colloidal gel. The material is dried at 120 ° C in air prior to use.

Experiment 17 CoCrTiO COQ, 2 Cr0.2 (Ti? 2-x (OH) 2?) 14. 57 ml of a 60% by volume solution in ethanol containing titanium n-butoxide [Aldrich, 24-411-2] are added to 52.68 ml of ethanol. 8.50 ml of a 1.5 molar, aqueous solution of chromium hydroxide acetate [Aldrich, 31,810-8] and 12.75 ml of a 1.0 M aqueous solution of cobalt chloride [Alpha 12303], were added to the alkoxide solution. During the addition, the glass vessel was gently swirled under an atmosphere of inert nitrogen. The gelled material was dried at 120 ° C in air prior to use.

Experiment 18 TiSiO Tio.1Si0.9 (02-x (OH) 2x) 1. 915 ml of a solution of tetraethyl orthosilicate (Aldrich, 13,190-3) containing 60% by volume alkoxide in ethanol, are added to 26.43 ml of titanium n-butoxide (Aldrich, 24,411-2) which also contains 60% in volume of the alkoxide in ethanol. 67.43 ml of ethanol are added to form a mixed alkoxide solution. The solution is maintained under a nitrogen atmosphere. A solution containing 3,712 ml of water mixed with 0.515 ml of glacial acetic acid (EM Sciences, X0409PS-1) is added to the alkoxide solution. During the addition of the aqueous components, the glass vessel was gently swirled under an atmosphere of inert nitrogen. A gelatinous white gel formed almost immediately during the addition and was allowed to stand at room temperature for at least 24 hours. The gelled material is dried at 120 ° C in air prior to use.

Experiment 19 CoSiTiO CQQ.5 Ti0.4 Sip.i (Q2-x (OH) 2x i 0.5 3. 86 ml of 60% by volume TEOS, 23,661 ml of 60% by volume titanium n-butoxide, and 16.45 ml of ethanol were used to form the alkoxide solution. To this solution, 3.74 ml of H20, 0.425 ml of glacial acetic acid, and 51.879 ml of a 1.0 M solution of cobalt chloride (I) (Alfa, 12303) in ethanol are added while stirring gently in a swirl glass container. A nitrogen gas layer was used from start to finish. A reddish blue gelatinous material was produced. After resting 24 hours in air, the material is dried at 120 ° C prior to the CHHP decomposition evaluations.

Experiment 20 AuMgCrTiO AUQ. QQ495 go .0099 Crp. QQ4 95 (TÍQ2-? (OH) 2x) or .9e 46. 14 ml of ethanol (Quantum Chemical, 290, Newark, NJ, scrupulously dehydrated) were combined with 20,214 ml of a 60% by volume solution in ethanol, containing titanium butoxide (Aldrich, 24,411-2), under an atmosphere of inert nitrogen. 0.818 ml of a 0.219 M aqueous solution containing AuCl3 (Aldrich, 33,404-9) (prepared using water and a 3: 1 molar ratio of HCl.Au of 37% by weight HCl, EM Sciences, Gibbstown, NJ) is add simultaneously with 2.00 ml of 0.179 M aqueous magnesium citrate (Alpha, 39368), (0.119 ml of 1.5 M aqueous chrome hydroxide acetate, Cr3 (OH) 2 (CH3COO) 7 (Aldrich, 31.810-8), and 0.709 ml of glacial acetic acid, (JT Baker, 6903-05, Phillipsburg, NJ) Aqueous solutions were added simultaneously to the alkoxide solution.The vessel was swirled gently during this addition. Turbid green / white color After resting for at least 24 hours in air, the material was dried at 120 ° C in a vacuum oven, and subsequently calcined at 250 ° C in air for five hours, prior to the evaluations of decomposition of CHHP.

Experiment 21 AuMgCrTio AUQ, Q227 go.0909 Cr0.Q22 (TÍ0 -x (OH) 2?) 0.8636 The same procedure and reagents were used as described for Experiment 20, with the following differences: 3.216 ml of AuCl3 solution 15.243 ml of titanium n-butoxide solution 15.749 ml of magnesium citrate solution 0.469 ml of acetate solution of chromium hydroxide 34.789 ml of ethanol 0.535 ml of glacial acetic acid A cloudy green / white gel was produced, and treated in the same manner as described for Experiment 20.

Experiment 22 AuMgCrZrO AUp, QQ95 Mgp. p 76 Crp.o95 (ZrQ2_x (OH) 2x) Q.848 1. 836 ml of ethanol (Quantum Chemical, 290, Newark, NJ, scrupulously dehydrated) is combined with 65,530 ml of a 0.558 M solution in ethanol containing zirconium n-propoxide (Alfa, 22989) under an inert nitrogen atmosphere and 1.827 ml of a 0.2248 M aqueous solution are added simultaneously. contains AuCl3 (Aldrich, 33,404-9) with 11,408 ml of a 0.180 M solution of aqueous magnesium citrate (Alpha, 39368), and 2738 ml of 1.5 M aqueous chromium hydroxide acetate, Cr3 (OH) 2 (CH3COO) 7 (Aldrich, 31,810-8). The aqueous solutions were added simultaneously to the alkoxide solution. The vessel was gently swirled during this addition. A cloudy yellow / white gelatinous material was produced. After standing for at least 24 hours in air, the material is dried at 120 ° C in a vacuum oven, and subsequently calcined at 250 ° C in air for five hours, prior to CHHP decomposition evaluations.

Experiment 23 AuMgCrAlO AUQ, 0095 Mgo. Q476 Crp. 0952 (A10? .5-X (OH) 2x) Q, 8 76 69. 574 ml of a 0.05 M solution, in ethanol, of aluminum isopropoxide (Aldrich, 22.904-7) are added to the reaction vessel. In a second step, 0.525 ml of a 0.0744 M aqueous solution containing AuCl3 (Aldrich, 33,404-9) were added simultaneously with 1086 ml of 0.180 M aqueous magnesium citrate (Alpha, 39368), 0.361 ml of chromium hydroxide acetate aqueous 1.5 M, Cr 3 (OH) 2 (CH 3 CO 0) 7 (Aldrich, 31,810-8). The aqueous solutions were added simultaneously to the alkoxide solution. The vessel was gently swirled during this addition. A red, cloudy gel was produced. After resting for at least 24 hours in air, the material is dried at 120 ° C in a vacuum oven, and subsequently calcined at 250 ° C in air for five hours, prior to CHHP decomposition evaluations. This Experiment produced an aluminum-based mixture of hydroxides and oxides.

Experiment 24 AuMgCr lO uo .0952 Mg0. Q476 Cr0, 19o (AlO? .5-x (OH) 2x) 0, 7524 The same procedure was used in Experiment 23, except for the volume changes listed below. A red, cloudy gel was produced. 0.592 ml of AuCl3 solution 69.552 ml of the aluminum isopropoxide solution 1.223 ml of 0.587 ml sodium citrate solution of the chromium hydroxide acetate solution Experiment 25 AuCrAlO AUp.o! Crp.Q! (A101.5 -? (OH) 2x)? 98 2500 ml of isopropanol (EM Sciences, PX1835-6) are combined with aluminum isopropoxide (Aldrich, 22.904-7) in a N2 drying box of inert atmosphere. Solid isopropoxide dissolved in isopropanol for a period of 24 hours. In a separate step, 0.3731 g of AuCl3 (Aldrich, 33, 40-9) are dissolved in 25 ml of ethanol (Quantum Chemical, Newark, NJ, scrupulously dehydrated). A third solution containing 0.246 g of Cr3 (OH) 2 (CH3COO) 7 (chromium hydroxide acetate, Aldrich, 31.810-8) and 0.85 ml of water (mixed with 8 ml of ethanol) was prepared. The aluminum alkoxide solution is loaded into a resin pan, and placed under a layer of nitrogen that is flowing. The solution containing the gold trichloride is transferred to a dropping funnel and added to the aluminum isopropoxide solution while stirring. The aqueous solution containing the chromium hydroxide acetate is then added to this mixed solution. Following the hydrolysis, the solution was clear. A gel point was observed after approximately twenty-four hours under nitrogen. The final material was dark red, and dried at 120 CC under vacuum. The xerogel was subsequently calcined at 250 ° C in air for 5 hours prior to use.

Experiment 26 CrAlO Cr0.01 (A10? .5-x (OH) 2?) ?. 98 The same procedure was used as in Experiment 25, except that the gold salt was not added. 10,213 g of aluminum isopropoxide are combined with 1,000 ml of isopropyl alcohol. 0.1026 g of chromium hydroxide acetate are dissolved in 0.5 ml of H20, and then diluted with 3 ml of ethanol. A gelling point is carried out in 24 hours. The final xerogel was green, after drying under vacuum at 120 ° C. The material is calcined at 250 ° C in air prior to use.

Experiment 27 AuMgCoTiO Aup.pi Mgo.ps Cr0.2 (TiQ2_-x (OH) 2x) 0.79 Under an inert nitrogen atmosphere, 14,878 ml of 60% by volume in ethanol, containing titanium n-butoxide (Aldrich, 24,411-3) are added to a reaction vessel. Separate solutions containing 5,013 ml of a 0.0659 M AuCl3 solution (prepared by dissolving AuCl3 (Aldrich, 33.440-9) in ethanol), 33,033 ml of 0.2 M ethanolic CoCl2 solution (prepared by dissolving the CoCl2 * 6H20 Fisher, C- 371 in ethanol) and 9,176 ml of 0.180 M magnesium citrate solution (prepared by dissolving the magnesium citrate pentahydrate in water) were prepared. The three solutions were added simultaneously to the alkoxide solution. The container is gently swirled during this addition. A purple solution formed; a gel point could be obtained in 24 hours. After drying under vacuum at 120 ° C, a purple xerogel was formed. The material was calcined in air at 250 ° C for 5 hours prior to use.

Experiment 28 CoCrZrC Cup Crp.3 (ZrQ2-x (OH) gx) q ^ e . 1935 g of cobalt chloride (CoCi2, Alpha, 12303, anhydrous), 24.1328 g of chromium hydroxide acetate (Cr3 (OH) 2 (CH3COO) 7, Aldrich, 31.910-8) are dissolved in 40 ml of H20 and 183.51 ml of ethanol (scrupulously dehydrated). In an inert atmosphere drying box, 78.6192 g of zirconium n-propoxide (Alfa, 22989) are combined with 183.51 ml of ethanol and placed in a resin pan under flowing nitrogen. The aqueous solutions containing the cobalt chloride and the chromium hydroxide acetate were slowly added to the zirconium alkoxide solution, with stirring. A viscous, cloudy gel formed almost immediately during hydrolysis. The material was dried under vacuum at 120 ° C, as previously described.

Experiment 29 CrAlO Cr0.?(A10?.5-?(OH)2x)o.9 Under an inert nitrogen atmosphere, 25,966 ml of an aluminum oxide sol (Nyacol, Al-20, 20 wt.% Of A1203 in water) are added to a reaction vessel in the company of 7.97 ml of a solution of sodium acetate. 1.698 M aqueous chromium hydroxide (Aldrich, 31,810-8). A dark black gel formed almost immediately (over the course of minutes). The material was dried under vacuum, as described above, prior to use.

Experiment 30 CoNBTiO C? P.3 (NbO? .5-x (OH) 2x) o.o? (TÍ02-x (OH) 2x) o.69 Under an inert nitrogen atmosphere, 34.092 ml of anhydrous ethanol is added to 18182 ml of a 60% by volume solution in ethanol, containing titanium n-butoxide (Aldrich, 24.411-3) in the company of 1.52 ml of a 0.304 M ethanolic solution of niobium ethoxide prepared by reacting the NbCls with ethanol (Johnson-Matthey, 11548). Separate solutions containing 13,866 ml of 1.0 M ethanolic CoCl 2 solution (prepared by dissolving CoCl 2 »6H 20, Alpha, 36554) and 2,339 ml of H 2 O were prepared. The two solutions were added simultaneously to the alkoxide solution. The vessel was gently grasped during this addition. A blue solution was formed; a gel point could be obtained in 24 hours. After drying under vacuum at 120 ° C, a blue xerogel was formed.

Experiment 31 AuCrTiO Auo.oi Cr0.2 (TiQ2-x (OH) 2x) or, 79 Under an inert nitrogen atmosphere, 53,128 ml of ethanol (meticulously obtained) are added to 33,235 ml of a 60% by volume solution, in ethanol, containing titanium n-butoxide (Aldrich, 24,411-3). Separate solutions containing 22.726 ml of a 0.03247 M AuCl3 solution (prepared by dissolving AuCl3 (Aldrich, 33.440-9) in ethanol, 9.839 ml of a 1.5 M aqueous chrome hydroxide acetate solution (prepared by dissolving Cr3 (OH) 2 (CH3COO) 7 (Aldrich, 31.810-8) in water)) were prepared. The two solutions were added simultaneously to the alkoxide solution. The vessel was gently swirled during this addition. A dark green / purple solution formed; a gel point could be obtained in 24 hours. After drying under vacuum at 120 ° C, a dark green purple xerogel was formed. The material was calcined in air at 250 ° C for 5 hours prior to use.

Experiment 32 AuAlO AUo.Qi (A10? .5 -? (OH) 2?)? 98 The same procedure as that of Experiment 25 was used, except that the chromium salt was not added. 10,213 g of aluminum isopropoxide are combined with 1,000 ml of isopropyl alcohol, 0.1548 g of AuCl3 are dissolved in ethanoi. A gelling point is obtained in 24 hours. The final xerogel was dark red / purple in color, after drying under vacuum at 120 ° C. The material was calcined at 250 ° C prior to its bear.

EXAMPLES All reactions were run in a batch reactor mode, in 3.5 ml glass vials, sealed with plastic stoppers and partitions. The ampoules were inserted into an aluminum block stirrer / heater that can hold up to 8 ampoules. Agitation was done using stir bars coated with Teflon®.

Each vial was charged first with 1.5 ml of n-octane or undecane solvent, approximately 0.005 or 0.01 g of a given crushed catalyst, a stir bar and the vial is sealed. The ampules were shaken and heated for approximately 10 minutes to ensure that the desired reaction temperature of 125 ° C had been achieved. Next, at the beginning of each example, 30 μi of a storage solution of CHHP and TCB (1,2,4-trichlorobenzene) or CB (chlorobenzene), from the internal standard of GC (gas chromatograph) were injected. The storage solutions consisted of mixtures of approximately 20% by weight of TCB or CB in CHHP. The source of CHHP contained up to 2.0% by weight of cyclohexanol and cyclohexanone combined. The ampules were removed from the aluminum stirrer / heater after a period of 0.5 to 10 minutes and allowed to cool to room temperature. In Examples 1-10 (Table I) the ampoules were analyzed directly to verify the amount of remaining CHHP, using a DB-17 capillary column of 15 m with an internal diameter of 0.32 mm. The liquid phase of the column was comprised of methyl polysiloxane (50% by weight of phenyl). The column was obtained from J. and W. Scientific, Folsum, California.

GC analyzes to verify the amounts of CHHP in each solution were calculated using the equation:% weight CHHP = (% CHHP area /% TCB area) x% TCB x R weight. F. CHHP R.F.CHHP (CG response factor for CHHP) was determined from the calibration solutions containing known amounts of CHHP and TCB, and was calculated from the equation: R.F.CHHP =% weight CHHP /% area CHHP% weight TCB /% area TCB % CHHP Decomp. = 100 x [l - (% CHHP area /% TCB area) final / (% CHHP area /% initial TCB area] In Examples 1-10 (Table 1) the initial concentrations of CHHP in each vial were approximately 2.2% The numbers of CHHP? nic? a? and CHHPfina? of% by weight of CG are only approximate because the number of TCB ratios per g of solution used in the CG calculations were all made arbitrarily equal to 0.25 mg of TCB / g of solution. Since the unheated samples of 1.5 ml of n-octane and 30 μl of the CHHP / TCB solution were analyzed with each set of the CHHP decomposition product ampoules from the same CHHP / TCB solution, they could be calculate the exact changes in the CHHP / TCB relationships. Examples 11-13 (Table II), and Examples 14-16 (Table III), gave the results of the decomposition of the% of t-butyl hydroperoxide (t-BuOOH) and the% of eumeno hydroperoxide (CumenoOOH) of the batch, respectively for the catalysts of 1% Au / Coal and 10% Au / Si02. Analyzes for t-BuOOH and CumenoOOH were made using a well-known iodometric titration procedure, described in Comprehensi ve Analytcal cal Chemistry, Elsevier Publishing Company, New York, Eds. C. L. Wilson, p. 756, 1960. The starting and product solutions of t-BuOOH and cumenoOOH in n-octane, followed by the addition of excess acetic acid / KI solution, were shaken in sealed vials at room temperature for 10 minutes and were titrated with a 0.1M Na2S203 solution for the amounts of I2 released by t-BuOOH and CumenoOOH present. Examples 17-41 (Tables IV and V) were run as described for Examples 1-10 except that the reaction was run at 150 ° C and chlorobenzene was used as an internal CG standard instead of the TCB and the solvent of undecano was used in place of n-octane. In Tables IV and V, the amount of initial CHHP and final CHHP in the reaction was determined by calculating the CG peak area of CHHP divided by the C-tocopherol C peak area (% CHHP area /% CB area).

TABLE I * Weight Weight Weight Method Approx. Temp. Time CHHP CHHP ^ Desc.

Ex. Catalyst, g of Prep. CHHP Reac. ° C min. init Final CHHP 1 1.4% Au / Coal, Exp. 2.2 125 10 0.407 0.221 45.7 0. 0100 2 1.4% Au / Coal, Exp. 1 2.2 125 10 0.537 0.281 47.7 0. 0103 3 1.4% Au / SiO, 0.0101 Exp. 2 2.2 125 10 0.407 0.391 3.9 4 1.4% Au / SiO, 0.0101 Exp. 2 2.2 125 10 0.537 0.430 19.9 14% Au / Si0, 0.0102 Exp. 3 2.2 125 10 0.407 0.154 62.2 6 14% Au / SiO ", 0.0104 Exp. 3 2.2 125 10 0.407 0.131 67.8 7 0% Au / SiO .., 0.0103 Exp. 4 2.2 125 10 0.407 0.379 '6.9 8 1.4 * Au / Al203, 0.0102 Exp. 5 2.2 125 10 0.537 0.449 16.4 9 13% Ag / SiO ?, 0.0102 Exp. 6 2.2 125 10 0.407 0.245 39.8 10 4.5% Cu / SiO, 0.0103 Exp. 7 2.2 125 10 0.407 0.119 70.8 TABLE II 'Weight * Weight Method Temp. Time t-BuOOH t-BuOOH Desc.

Ex. Catalyst, g of Prep. Reac. ° C min. init Final t-BuOOH 11 1.4'.Au / Carbon, Exp. 125 10 0.35 0.20 44 0.0102 12 14iAu / SiO ^, 0.0102 Exp. 3 125 10 0.35 0.1E 48 13 none 125 10 0.33 TABLE III * Weight x Weight t-Cumeno-t-Cumeno- Temp. Time (OOH) (OOH) *; Desc.

Ex. Catalyst, Prep q. Reac. ° C min. init Final t-BuOOH 14 1.4% Au / Coal, Exp. 1 125 10 0.55 0.32 42 0.0103 15 14 »Au / Si02, 0.0103 Exp. 3 125 10 0.55 0.30 45 16 none 125 10 0.55 0.54 2 TABLE IV - Weight CHHP / CHHP / Approx. Temp. Time CB CB Desc Ex. Prep catalyst CHHP Reac. ° C min. init Final CHHP 17 l * Au / MgO, 0.0102 Exp. 8 2. .2 150 5 3.41 3.29 3.5 18 l% Au /? - Al2? 3, 0.0120 Exp. 9 2: .. 22 150 5 3.41 0 100 19 l% Au / SiO. , 0.0101 Exp. 10 2. .22 15C 5 3.41 0.91 73.3 l% Au / TiO, 0.0106 Exp. 11 2. .22 150 5 3.41 2.26 33.6 21 l Au / ZrO., 0.0054 Exp. 12 2 150 0.5 5.26 4.68 11.1 22 l% Au, 0.1 ^ Pd / Al2O ,, Exp. 13 2 150 0.5 4.82 3.01 37.5 0. 0051 TABLE V Weight CHHP / CHHP / Approx. Tenp. Time CB Desc.

ET. Catalyst, g of Prep. CHHP Reac. ° C pun. ínic. Final CHHP 23 CrZrO, 0.0099 Exp. 14 150 5.0 5.94 0.44 92.6 24 CrTaO, 0.010 Exp. 15 150 5.0 5.94 0.36 93.6 CrTiO, 0.0109 Exp. 16 150 5.0 4.55 0.00 100 26 CoCrTlO, 0.0110 Exp. 17 130 2.0 5.30 0.00 100 27 TiSiO, 0.0054 Exp. 18 150 0.5 4.59 4.05 11.8 28 C0S1T1O, 0.0050 Exp. 19 150 0.5 5.57 0.08 98.5 29 AuMgCrTiO, 0.0055 Exp. 20 150 0.5 4.64 4.32 7.0 AuMgCrTlO, 0.0056 Exp. 21 150 0.5 4.64 3.94 15.1 31 AuMgCrZrO, 0.0054 Exp. 22 150 0.5 5.18 3.96 23.6 32 AuMgCrAlO, 0.0051 Exp. 23 150 0.5 5.15 3.16 38.6 33 AuMgCrAlO, 0.0053 Exp. 24 150 0.5 5.15 2.62 49.2 34 AuCrAlO, 0.0051 Exp. 25 150 0.5 5.5- 2.65 35 CrAlO, 0.0054 Exp. 26 150 0.5 5.52 5.24 6.9 36 AuMgCoTiO, 0.0053 Exp. 27 150 0.5 5.28 1.23 76.6 37 CoCrZrO, 0.0052 Exp. 28 150 0.5 5.26 0.54 88.7 38 CrAlO, 0.0056 Exp. 29 150 0.5 5.26 2.61 50.4 39 COnBTIo, 0.0054 Exp. 30 150 0.5 5.57 3.30 40.8 40 AuCrTiO, 0.0054 Exp. 31 150 0.5 5.43 4.34 20 41 AuAlO, 0.0053 Exp. 32 150 0.5 5.52 4.86 11.9 Although the particular embodiments of the present invention have been described in the foregoing description, it will be understood by those skilled in the art that the invention is capable of numerous modifications, substitutions and rearrangements without departing from of the spirit or the essential attributes of the invention. Reference should be made to the appended claims, rather than to the preceding specification, such as those indicating the scope of the invention.

It is noted that in relation to this date the best method known by the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, property is claimed as contained in the following

Claims (18)

1. An improved process for the decomposition of a hydroperoxide, to form a decomposition reaction mixture containing a corresponding alcohol and ketone, the improvement is characterized in that it comprises the decomposition of a hydroperoxide by contacting the hydroperoxide with a catalytic amount of a catalyst heterogeneous selected from the group consisting of (a) gold, (b) silver, (c) copper and (d) sol-gel compounds comprised of (i) one or more elements selected from a first group consisting of Cr, Co and Ti and (ii) one or more elements selected from a second group consisting of Zr, Ta, Nb, Si, Al, Mg and Ti, wherein the selected elements of (ii) are combined with an oxide and wherein the Elements of the first group can not be the same as the elements of the second group.

2. The process according to claim 1, characterized in that the heterogeneous catalyst is supported on a catalyst support element.

3. The process according to claim 2, characterized in that the catalyst support element is selected from the group consisting of Si02, A103, carbon, Ti02, MgO, and zirconia.

4. The process according to claim 1, characterized in that the hydroperoxide is the cyclohexyl hydroperoxide.

5. The process according to claim 1, characterized in that the temperature of the decomposition reaction is from about 80 ° C to about 170 ° C, and the pressure of the decomposition reaction is from about 69 kPa to about 2760 kPa.

6. The process according to claim 5, characterized in that the pressure of the reaction is from about 276 kPa 'to about 1380 kPa.

7. The process according to claim 1, characterized in that the reaction mixture contains from about 0.5 to about 100 weight percent of cyclohexyl hydroperoxide. '

The process of i according to claim 1, characterized in that the process is carried out in the presence of cyclohexane.

9. The process according to claim 1, characterized in that the process is carried out in the presence of added oxygen.

10. The process of I according to claim 2, characterized in that the catalyst is gold. i

11. The process of | according to claim 10, characterized in that the gold is supported on zirconia.

12. The process according to claim 10, characterized in that the gold is from about 0.1 to about 10 weight percent of the catalyst and the support element.

13. The process according to claim 10, characterized in that the Pd is also present with the gold.

14. The process according to claim 10, characterized in that gold is present on the support element as well as well dispersed particles having a diameter from about 3 nm to about 15 nm.

15. The process according to claim 1, characterized in that the gold catalyst is in the form of a sol-gel compound.

16. The process according to claim 15, characterized in that the gold catalyst is in the form of a sol-gel compound comprising Au and Cr.

17. The process according to claim 1, characterized in that the sol-gel compound contains Cr and / or Co.

18. The process according to claim 1, characterized in that the oxide is in an inorganic matrix of hydroxides or oxides, or combinations thereof.