GB743458A - A process for the regeneration of a catalyst accelerating the binding of oxygen to hydrogen - Google Patents

Abstract

A catalyst which accelerates the reaction between oxygen and hydrogen, and which has become polluted by deposited sulphur during use for removing free oxygen above a critical concentration from a gas containing also hydrogen and hydrogen sulphide, is regenerated by treatment with the gas in which the oxygen content has been reduced below the critical concentration by passing through the unpolluted catalyst. The critical oxygen concentration for a catalyst at a particular temperature is that at which the amount of sulphur formed by the reaction of hydrogen sulphide with oxygen is equal to the amount of sulphur removed by evaporation and reaction with hydrogen. A suitable catalyst comprises at least one of the metals molybdenum and tungsten in the form of sulphide and/or oxide, a promoter containing at least one of the metals iron, cobalt, nickel, chromium, vanadium, and uranium in the form of sulphide and/or oxide, and a carrier of alumina, silica gel, or synthetic or natural aluminium silicate. Preferred temperatures for regeneration are 200-360 DEG C. The mass of catalyst used for oxygen removal may be divided into two parts, and when one part has become polluted, the gas flow is reversed so that the oxygen-free gas obtained is used as the regenerating gas. Alternatively, the regenerating gas may be passed through the bed until a sufficiently thick layer thereof has been regenerated, then raw gas is substituted for regenerating gas. A system may be employed which includes multi-step reactors as described in Specification 742,912. The gas treated may be rich in hydrocarbons and obtained, for example, by the dry distillation of shales. Specification 719,791 also is referred to.