摘要:
A hydrophobic composite Pd-membrane catalyst, useful for the non-hazardous direct oxidation of hydrogen by oxygen to hydrogen peroxide, without a gas phase mixing of hydrogen and oxygen or air, having the general formula: HPM (c)/SOMF (b)/MxPd1−x (a)/IPM wherein, IPM is an inorganic porous membrane, MxPd1−x is a metal alloy, permeable only to hydrogen gas, Pd is a palladium metal; M is a metal other than palladium, or a mixture of two or more thereof; x is a mole fraction of the metal M in the metal alloy (MxPd1−x), a, in the round bracket, is a weight of the metal alloy per unit area of IPM; SOMF is a surface oxidized thin metal film comprising palladium b, in the round bracket, is a thickness of SOMF; HPM is a hydrophobic polymer membrane and c, in the round bracket , is a weight of the HPM per unit area of SOMF and a process for producing the said catalyst.
摘要:
This invention provides a process for the activation of a metallic palladium containing catalyst which is useful for the direct oxidation of hydrogen by oxygen to hydrogen peroxide, by treating the catalyst with an oxidising agent in order to at least partially oxidise the metallic palladium contained in the catalyst to palladium (TT) oxide. The selectivity and yield of the catalyst for hydrogen peroxide are observed to increase substantially and the hydrogen peroxide decomposition activity of the catalyst is drastically reduced.
摘要:
The above objects are achieved by providing a novel process for the production of hydrogen peroxide, by the non-hazardous direct oxidation of hydrogen by oxygen to hydrogen peroxide, without the formation of an explosive H2 and O2 gas mixture, using a novel tubular hydrophobic composite Pd-membrane catalyst, represented by a formula: HPM (c)/SOMF (b)/MxPd1−x(a)/IPM Wherein: IPM is an inorganic porous membrane, permeable to all gases and vapors, in a form of tube having a thickness of at least 0.5 mm and internal diameter of at least 0.6 cm; Mx Pd1−x is a metal alloy, permeable only to hydrogen gas, deposited on the inner side of IPM; Pd is a palladium metal; M is a metal selected from copper, silver, gold, noble metals other than palladium, or a mixture of two or more thereof; x is a mole fraction of the metal M in the metal alloy (MxPd1−x) in the range from about 0.03 to about 0.6; (a) is a weight of the metal alloy per unit area of IPM in the range from about 5.0 g.m−2 to about 500 g.m−2; SOMF is a surface oxidized thin metal film comprising palladium which is permeable only to hydrogen, deposited on the metal alloy (Mx Pd1−x); (b) is a thickness of SOMF in the range from about 0.05 &mgr;m to about 5.0 &mgr;m; HPM is a hydrophobic polymer membrane permeable to hydrogen and oxygen gases and also to vapors of water and hydrogen peroxide but not to liquid water or aqueous solution; and (c) is a weight of the HPM per unit area of SOMF in the range from about 0.2 g.m−2 to about 40 g.m−2.
摘要:
The present invention relates to a novel hydrophobic multicomponent catalyst useful in the direct oxidation of hydrogen to hydrogen peroxide and to a method for the preparation of such catalyst. More specifically, this invention relates to a novel hydrophobic muticomponent catalyst comprising a hydrophobic polymer membrane deposited on a Pd containing acidic catalyst, useful for the direct oxidation of hydrogen by oxygen to hydrogen peroxide, an a method for preparing the same.