Abstract: Chlorine is prepared by catalytic oxidation of a hydrogen chloride stream having a content of sulfur in elemental or bonded form of less than 100 ppm, preferably less than 50 ppm, more preferably less than 5 ppm, most preferably less than 1 ppm, based on the weight of the hydrogen chloride stream.

Abstract: Processes for the production of chlorine from a gas containing hydrogen chloride and carbon monoxide, which comprise the catalysed oxidation of the carbon monoxide as well as optionally further oxidizable constituents, with oxygen to form carbon dioxide in an upstream reactor under adiabatic conditions.

Abstract: Processes for separating carbon monoxide from a hydrogen chloride-containing gas, which comprise reacting the carbon monoxide with chlorine to form phosgene and then optionally separating the phosgene from the hydrogen chloride-containing gas. The hydrogen chloride-containing gas that is used preferably derives from a phosgenation or isocyanate forming reaction.

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: Chlorine is prepared by catalytic oxidation of a hydrogen chloride stream having a content of sulfur in elemental or bonded form of less than 100 ppm, preferably less than 50 ppm, more preferably less than 5 ppm, most preferably less than 1 ppm, based on the weight of the hydrogen chloride stream.

Abstract: Processes comprising: providing a gas stream comprising hydrogen chloride and carbon monoxide; and oxidizing at least a portion of the carbon monoxide in the gas stream in the presence of a catalyst to form a product gas comprising hydrogen chloride and carbon dioxide; wherein the catalyst comprises tin dioxide and a ruthenium compound comprising at least one element selected from the group consisting of oxygen and chlorine.

Abstract: Processes comprising: providing a crude gas comprising hydrogen chloride and at least one sulfur compound; and passing the crude gas across a sacrificial material such that at least a portion of the at least one sulfur compound is oxidized and precipitated as sulfate onto the sacrificial material to provide a hydrogen chloride product gas.

Abstract: A process is disclosed comprising: (a) reacting hydrogen chloride and oxygen to form a gas mixture comprising chlorine, water, unreacted hydrogen chloride, and unreacted oxygen; (b) cooling the gas mixture to form an aqueous solution of hydrogen chloride; (c) separating at least a portion of the aqueous solution of hydrogen chloride from the gas mixture; (d) removing at least a portion of the water from the gas mixture; and (e) subjecting the gas mixture to a gas permeation such that at least a portion of the unreacted oxygen in the gas mixture is separated to form a chlorine-rich gas stream and an oxygen-containing partial stream.

Abstract: Processes for separating carbon monoxide from a hydrogen chloride-containing gas, which comprise reacting the carbon monoxide with chlorine to form phosgene and then optionally separating the phosgene from the hydrogen chloride-containing gas. The hydrogen chloride-containing gas that is used preferably derives from a phosgenation or isocyanate forming reaction.

Abstract: Processes for the production of organic isocyanates, comprising the production of phosgene by reaction of CO with Cl2, the reaction of the phosgene with organic amines to form the organic isocyanates, and the separation of the organic isocyanates, which is characterised in that the carbon monoxide is removed from the HCl-containing waste gas from the isocyanate synthesis by reaction with chlorine to form phosgene. The phosgene can be separated off and can optionally be fed back into an isocyanate synthesis The HCl-containing, CO-depleted gas is preferably subjected to HCl oxidation (Deacon). A closed chlorine cycle can be used in the isocyanate synthesis.

Abstract: A process is disclosed comprising: (a) reacting hydrogen chloride and an oxygen-containing gas to form a gas mixture comprising chlorine, water, unreacted hydrogen chloride, and unreacted oxygen, wherein the oxygen-containing gas reacted with the hydrogen chloride has an oxygen content of not more than 99 vol. %; (b) cooling the gas mixture to form an aqueous solution of hydrogen chloride; (c) separating at least a portion of the aqueous solution of hydrogen chloride from the gas mixture; and (d) subjecting the gas mixture to a gas permeation to form a chlorine-rich gas stream and an oxygen-containing partial stream.