Abstract: The description relates to an abrasion-resistant carrier catalyst for removing the nitrite and/or nitrate content of polluted water with selective nitrogen formation. The catalytically active metal component is palladium and/or rhodium or palladium and a metal from the copper group. The carrier consists of aluminum oxide in the "theta" and "kappa" modification and has either one maximum pore diameter in the 70 to 150 nm (700 to 1500 .ANG.) range or two maxima in the 10 to 150 nm (100 to 1500 .ANG.) range. The description also relates to a continuously operable process for the removal or reduction of the oxygen, nitrite and/or nitrate content of water by catalytic hydrogenation. The process is implemented using the novel carrier catalysts, the carriers being made of aluminum oxide of the theta and kappa modifications. Contamination of the catalyst is effectively prevented by the preferred use according to the fluidized bed process.

Abstract: A process for treating waste water containing chlorinated organic substances, particularly waste water from production of epichlorohydrin which contains more than 10 mg of adsorbable organic halogen compounds (AOX) per liter, comprising charging the waste water at a pH of 10 to 14 (measured at room temperature) into a reactor and maintaining a temperature of at least 75.degree.C., a pressure of at least 1 bar (abs.), and a residence time of at least 0.5 hours in said reactor, thereby partially dechlorinating and/or dehydrochlorinating chlorinated organic compounds contained in the waste water, and thereafter subjecting the waste water to further dechlorination and/or dehydrochlorination treatment in the presence of a hydrogen-containing gas, a hydrogen-releasing compound and/or a catalytically active material; and optionally subjecting the waste water to a biological treatment with the use of microorganisms; and apparatus for carrying out the foregoing process.

Abstract: A process for degerminating and treating aqueous liquids with gas having improved efficiency and an apparatus for simultaneously degerminating and gas treating liquids are described.

Abstract: A catalyst is disclosed made from a porous inorganic carrier material impregnated with a metal component selected from palladium, rhodium, mixtures of palladium and rhodium, and mixtures of palladium and a metal of the copper group, in which the carrier has a bimodal pore radius distribution with a first pore radius distribution maximum in the range of up to 400 .ANG., preferably 50 to 350 .ANG., and with a proportion of at least 20%, relative to the overall pore volume, of macropores having a radius of at least 2,000 .ANG., preferably 5,000 to 20,000 .ANG..

Abstract: The invention relates to particulate material for separation of metal cations from aqueous solutions. These particles contain complexing agents dispersed in a continuous aqueous phase which is embedded in or is a constituent of a hydrophilic gel and/or is encapsulated by a water-insoluble, ion-permeable shell.

Abstract: A continuously performable process for the removal or reduction of the nite and/or nitrate content of nitrite-polluted and/or nitrate-polluted water with the selective formation of nitrogen by catalytic hydrogenation. Catalysts suitable for carrying out such a process are also described.