Abstract: Hydrogen and carbon monoxide impurities are removed from a dry gas comprising the impurities, wherein the dry gas is at least substantially free of carbon dioxide, by passing the dry gas with sufficient residence time, e.g. at least 1.5 s, through a layer of catalyst comprising a mixture of manganese oxide and copper oxide. The use of expensive noble metal catalysts to remove hydrogen may thereby be avoided. In addition, regeneration of the catalyst using oxygen-containing regeneration gas does not reduce the effectiveness of the catalyst.

Abstract: Hydrogen and carbon monoxide impurities are removed from a dry gas comprising the impurities, wherein the dry gas is at least substantially free of carbon dioxide, by passing the dry gas with sufficient residence time, e.g. at least 1.5 s, through a layer of catalyst comprising a mixture of manganese oxide and copper oxide. The use of expensive noble metal catalysts to remove hydrogen may thereby be avoided. In addition, regeneration of the catalyst using oxygen-containing regeneration gas does not reduce the effectiveness of the catalyst.

Abstract: A back-up quantity of a “first” gas is supplied temporarily to maintain the level of production of the first gas from a cryogenic separation of a gaseous mixture comprising the first gas and at least one other gas in the event of reduction in the level of production of said first gas from the separation. In the event of reduction in the level of production of said first gas from the separation, liquefied first gas inventory is withdrawn from the or at least one of said cryogenic distillation systems and vaporised to produce said back-up quantity of first gas. The invention has particular application to the production of gaseous oxygen (“GOX”) from the separation of air.

Abstract: A back-up quantity of a “first” gas is supplied temporarily to maintain the level of production of the first gas from a cryogenic separation of a gaseous mixture comprising the first gas and at least one other gas in the event of reduction in the level of production of said first gas from the separation. In the event of reduction in the level of production of said first gas from the separation, liquefied first gas inventory is withdrawn from the or at least one of said cryogenic distillation systems and vaporised to produce said back-up quantity of first gas. The invention has particular application to the production of gaseous oxygen (“GOX”) from the separation of air.