Abstract: The present invention provides a process for producing chlorine by the catalytic gas phase oxidation of hydrogen chloride with oxygen, wherein the reaction is performed on at least two catalyst beds under adiabatic conditions, as well as a reactor system for performing the process.

Abstract: Process to recover ruthenium in the form of ruthenium halide, particularly ruthenium chloride, from a ruthenium-containing supported catalyst material comprising: a) chemically decomposing the ruthenium-containing supported catalyst material; b) producing a raw ruthenium salt solution; c) purifying the raw ruthenium salt solution and optionally stripping gaseous ruthenium tetroxide from the raw ruthenium salt solution; and d) treating the purified ruthenium compound obtained in c), particularly the ruthenium tetroxide, with hydrogen halide or hydrohalic acid to obtain ruthenium halide, particularly with hydrogen chloride or hydrochloric acid to obtain ruthenium chloride.

Abstract: Oxidation catalysts comprising one or more ruthenium compounds and one or more promoters selected from the group consisting of zirconium halides, alkali metal halides, alkaline earth metal halides and lanthanum compounds, wherein the molar ratio of promoter to ruthenium is in the range of from 1:100 to 1:1; as well as processes for their preparation and use.