Method of purifying a gas

Abstract

A method of purifying gas obtained by gasification of a biomass feedstock. The gas which contains carbon monoxide, carbon dioxide, hydrogen, hydrocarbons and mixtures thereof can be freed from impurities, such as hydrogen sulphide, hydrogen chloride, ammonia, carbonyl sulphide, hydrogen cyanide and mixtures thereof, by contacting the gas with an acidic aqueous wash solution of transition metal ions capable of binding to sulphide ions, by binding a significant portion of the hydrogen sulphide impurities contained in the gas into practically insoluble transition metal sulphide compounds to remove hydrogen sulphide impurities from the gas; and by separating the thus obtained purified gas from the aqueous solution. The purified gas is suitable for production of hydrocarbon compositions by, for example the Fischer-Tropsch process.

Dependencies are inferred from the claim text.