Abstract: Zerovalent Group VIII metals dispersed on titanium dioxide reduced and calcined at a temperature less than about 300.degree. C. are hydrothermally stable hydrogenation catalysts which may be used advantageously in the reduction of aqueous solutions of carbohydrates. The use of ruthenium on titanium dioxide in the hydrogenation of glucose affords sorbitol in excellent yields with quite high selectivity.

Abstract: Theta-alumina is a hydrothermally stable support which can be used advantageously as an inert carrier for metals effective as a hydrogenation catalyst, thereby affording means to conduct hydrogenation in aqueous media. Ruthenium on theta-alumina is especially effective in reducing aqueous solution of carbohydrates to their polyols with high conversion and, in the case of glucose, high selectivity to sorbitol.

Abstract: Surface-metallated aluminas and silicas are species many of whose physical properties, such as surface and pore volume, are unchanged but which exhibit superior hydrothermal stability. Suitable for use as catalytic supports, these materials can be simply prepared by treating the alumina or silica with a tetrahalide of a metal, such as titanium or zirconium, removing the unreacted tetrahalide, and calcining the resulting material in a moist atmosphere.

Abstract: Group VIII metals immobilized on an aminated polysaccharide in a highly dispersed state are active catalysts in the hydrogenation of unsaturated organic materials. Chitin and chitosan are preferred supports, with platinum and palladium among the more active Group VIII metals in hydrogenation.

Abstract: Support matrices are prepared by titanating the surface hydroxyl groups of refractory inorganic oxides with a titanium tetrahalide, such as TiCl.sub.4, reacting each of the remaining halogens of the surface-titanated oxide with one of the amino groups of diamine, and thereafter reacting the remaining amino group with one of the functional groups of a dialdehyde or diisocyanate. Titanating is carried out by contacting a refractory inorganic oxide with titanium tetrahalide, preferably in the absence of a solvent for the titanium tetrahalide, removing excess and unreacted titanium tetrahalide and heating the titanated inorganic oxide at a temperature of from about 80.degree. C. to about 200.degree. C. in an inert atmosphere of nitrogen, argon or helium, or in a vacuum. Such support matrices may be used to bind enzymes, affording effective immobilized enzyme systems.

Abstract: Zerovalent Group VIII metals dispersed on titanated alumina are hydrothermally stable hydrogenation catalysts which may be used advantageously in the reduction of aqueous solutions of carbohydrates. The use of ruthenium on titanated alumina in the hydrogenation of glucose affords sorbitol in excellent yields with quite high selectivity, and with minimal leaching of either ruthenium, titanium, or alumina.

Abstract: Polyhydroxylated compounds such as glucose, sucrose, sorbitol, etc. are subjected to a hydrogenolysis reaction at hydrogenolysis conditions which include a temperature in the range of from about 175.degree. to about 250.degree. C. and a pressure in the range of from about 10 to about 2000 pounds per square inch in the presence of a catalytic composition of matter. The catalyst comprises a carbonaceous pyropolymer possessing recurring units containing at least carbon and hydrogen atoms which is impregnated with a transition metal. The products which are obtained will include alcohols, acids, ketones, ethers, and hydrocarbons.

Abstract: Zerovalent Group VIII metals dispersed on titanium dioxide reduced and calcined at a temperature less than about 300.degree. C. are hydrothermally stable hydrogenation catalysts which may be used advantageously in the reduction of aqueous solutions of carbohydrates. The use of nickel on titanium dioxide in the hydrogenation of glucose affords sorbitol in excellent yields with quite high selectivity.

Abstract: Saccharides such as glucose, fructose, starch, etc. may be hydrogenated by treatment with hydrogen in the presence of a catalyst which comprises a metal of Group VIII of the Periodic Table composited on a support comprising a carbonaceous pyropolymer possessing recurring units containing at least carbon and hydrogen atoms at a temperature in the range of from about 90.degree. to about 150.degree. C. and a pressure in the range of from about 500 to about 3000 psi to obtain polyols. In such a manner, glucose may be hydrogenated to sorbitol and mannitol.

Abstract: Zerovalent Group VIII metals dispersed on alpha-alumina are hydrothermally stable hydrogenation catalysts which may be used advantageously in the reduction of aqueous solutions of carbohydrates. The use of ruthenium on alpha-alumina in the hydrogenation of glucose affords sorbitol in excellent yields with quite high selectivity, and with minimal leaching of either ruthenium or alumina.

Abstract: Group VIII metals immobilized on an aminated polysaccharide in a highly dispersed state are active catalysts in the hydrogenation of unsaturated organic materials. Chitin and chitosan are preferred supports, with platinum and palladium among the more active Group VIII metals in hydrogenation.

Abstract: This invention comprises a process for separating a carbohydrate from a feed stream comprising a mixture of carbohydrates. The separation is effected by contacting the feed stream with an adsorbent comprising a crystalline aluminosilicate or cation exchange resin, the exchangeable cationic sites of which are exchanged with cations of a rare earth metal. The adsorbed carbohydrate may subsequently be recovered by desorption with a desorbent material.

Abstract: Anhydrohexitols may be prepared from hexitols by heating the hexitols in the presence of metal ions whose charge to ionic radius ratio is from about 2.0 to about 3.2 at a temperature from about 100 to about 300.degree. C. A hexose, such as glucose, may be converted directly to anhydrohexitols, such as sorbitans, by hydrogenating the hexose in the presence of a suitable hydrogenation catalyst to which has been added an appropriate metal salt, such as nickel chloride.

Abstract: A composition comprising chitin or chitosan bearing a metal or mixture of metals deposited thereon in a highly dispersed state so as to immobilize said metal or mixture of metals is an effective catalyst for processes in which said metal or mixture of metals shows catalytic properties.