Abstract: The soot obtained in the form of a soot-containing aqueous waste liquor in the course of synthesis gas manufacture is utilizable bya) mixing said liquor in a sewage sludge treatment plant with a sewage sludge to which organic flocculants are added as drainage aids with or without a further quantity of finely divided coal or ash,b) filtering this pretreated sludge mixture,c) incinerating the resulting filter cake andd) burying the ash in a sanitary landfill.

Abstract: Carbon black and ash containing wastewaters from high-temperature processes in which the carbon black is present in an extremely finely divided and partly colloidal state are cleaned and disposed of by treatment with organic flocculants, predewatering of the flocculated suspension by gravity filtration and post-dewatering of the carbon black sludge by pressure filtration within the range from 0.5 to 15 bar in a process comprising adding sufficient calcium hydroxide to the wastewaters that the pH of an aqueous extract of the filter cake obtained is more than 11.8, preferably more than 12.0.

Abstract: Wastewaters which contain carbon black and ash and originate from high temperature processes and in which the carbon black is present in a very finely divided state and partially in a colloidal state are treated and disposed of by a process in which the wastewater is treated with calcium carbonate or calcium hydroxide and an organic flocculant and subjected to a two-stage filtration and the resulting filter cake containing carbon black and ash is subjected to an aftertreatment with an aqueous iron salt solution.

Abstract: An improved process for the manufacture of silver catalysts, in which the silver is applied to conventional dimensionally stable and chemically inert carriers, eg. alumina or quartz moldings, preferably by electroless deposition from silver salt solutions onto a great variety of surfaces acting as carriers, by the use of suitable reducing agents. In a particular embodiment, a uniform deposition of silver and a dense and well-adhering silver layer on the surface of the carrier are achieved by adding certain materials to the silver salt solutions.