摘要:
Moldings based on pyrogenic silicon dioxide with a pore volume of 0.5 to 1.8 ml/g are prepared by homogenizing pyrogenic silicon dioxide with methylhydroxyethyl cellulose, wax and polyethylene glycol with the addition of water, subjecting this mixture to a compounding and shaping process, extruding, optionally cutting the extrudate to the desired length using a cutting device, drying at a temperature of 70° to 150° C. and conditioning for a period of 30 minutes to 10 hours at a temperature of 400° to 1200° C. The moldings may be used as catalysts or catalyst supports for the preparation of vinyl acetate monomer, the hydration of ethylene and the hydration of propylene.
摘要:
Compacts based on pyrogenically produced silicon dioxide and having the following physical and chemical characteristics: Outer diameter 0.8-20 mm BET surface area 30-400 m2/g Pore volume 0.5-1.3 ml/g Breaking strength 10-250N Composition >99.8 wt. % SiO2 Other constituents
摘要:
The use of modified silicon dioxide as a catalyst support in catalytic reactions under hydrothermal conditions is described. The pore structure of the supports may be stabilized against hydrothermal reaction conditions by impregnating the catalyst supports with elements of Group IVB of the Periodic Tube of Elements.
摘要:
Moldings based on silica having a hollow cylindrical configuration with internal reinforcing stays or spokes leading from an inner wall of a hollow cylinder to the center of the molding or in the form of miniliths having passageway channels therethrough, are produced by homogenizing silica with methyl hydroxyethyl cellulose, wax and/or polyethylene glycol. Water and optionally aqueous alkaline ammonia solution are added, and the mixture is subjected to kneading and forming, extruding, optionally cutting the extrudate to the desired length by means of a cutting device, drying at a temperature from 20 to 150° C., and annealing for a period from 30 minutes to 10 hours at a temperature of 400 to 1200° C. The moldings can be used as catalyst supports for the production of unsaturated esters from olefins, organic acids and oxygen in the gas phase and and can be used in particular for the production of vinyl acetate monomer.
摘要:
Moldings based on pyrogenically produced mixed oxide having the following physicochemical parameters: External diameter 0.8-25 mm BET surface area 5-400 m2/g Pore Volume 0.2-1.8 ml/g Fracture strength 5 to 350 N Composition At least two oxides selected from the group SiO2, Al2O3, TiO 2 and ZrO2 in any desired combination but with the exception of SiO2/Al2O3 mixed oxides, in which > 75 wt. % of SiO2 is present. Other constituents
摘要:
Moldings are disclosed for use as a catalyst or catalyst support for hydrating olefin, such as ethylene and propylene. The moldings are based on a pyrogenically produced mixed oxide having the following physicochemical parameters: External diameter 0.8-25 mm BET surface area 5-400 m2/g Pore volume 0.2-1.8 ml/g Fracture strength 5 to 350 N Composition At least two materials selected from the group of SiO2, Al2O3, TiO2 and ZrO2 in any desired combination, with the proviso that when the combination is a SiO2/Al2O3 mixed oxide, at least 75 wt. % of SiO2 is present based on the total weight of the mixed oxide. Other constituents
摘要:
A catalyst and method of its production for use in making vinyl acetate monomer. The carrier is impregnated with a basic solution and a solution containing gold salts and palladium salts and finally impregnated with alkali acetate. The activity and selectivity of the catalyst, its mechanical strength, the noble-metal adhesion and the dispersion of noble metal on the carrier can be improved if the carrier is impregnated in a pretreatment with salts containing as cation elements of groups IA, IIA, IIIA and IVB of the periodic table and as anions elements of group VIIA or complex anions such as nitrate, sulfate or anions of organic acids such as acetate and lactate and is subsequently dried and calcined at temperatures of at least 160.degree. C.
摘要:
A catalyst for the dehydrogenation of C6.sub.6 -C.sub.15 paraffins is disclosed. The catalyst contains, on a support, at least one platinum group component, at least one promoter component from the group tin, germanium and lead, and at least one additional modifier. The additional modifier contains at least one alkaline earth metal. The stability of the catalyst is essentially higher than that achieved by conventional use of an alkali metal.
摘要:
A catalyst for the dehydrogenation of C.sub.6 -C.sub.15 paraffins is disclosed. The catalyst contains, on support, at least one platinum group component, at least one promoter component from the group tin, germanium and lead, and at least one additional modifier. The additional modifier contains at least one alkaline earth metal. The stability of the catalyst is essentially higher than that achieved by conventional use of an alkali metal.
摘要:
A process for the continuous catalytic conversion of organic compounds, that, together with unwanted attendant materials, form a starting substance: first the organic compounds of the starting material are purposely extracted by means of condensed fluids. Then the extract, containing the condensed fluids and organic compounds as the reaction mixture is contacted with a catalyst for the catalytic conversion of the organic compounds to form a product mixture, which contains the individual products of the catalytic conversion. The product mixture is separated from the reaction mixture and the fluids employed are, optionally, conducted back for extraction.