Patent ID: 7918922

Claim:
A process for removal of hydrogen sulphide, iron pentacarbonyl and nickel tetracarbonyl from a feed synthesis gas stream, comprising hydrogen sulphide, iron pentacarbonyl, and nickel tetracarbonyl, the process comprising the steps of: (a) removal of hydrogen sulphide and of iron pentacarbonyl from the feed synthesis gas stream by contacting the feed synthesis gas stream with an absorbing liquid comprising water, physical solvent and an amine, to obtain a synthesis gas stream depleted of hydrogen sulphide and depleted of iron pentacarbonyl; (b) adsorption of nickel tetracarbonyl by contacting the synthesis gas stream depleted of hydrogen sulphide and depleted of iron pentacarbonyl with a solid adsorbent comprising activated carbon to obtain a solid adsorbent enriched in nickel tetracarbonyl and a purified synthesis gas stream; and (c) thereafter desorption of nickel tetracarbonyl by contacting the solid adsorbent enriched in nickel tetracarbonyl with a CO-containing gas comprising at least 0.5 volume % CO to obtain regenerated adsorbent depleted of nickel tetracarbonyl and a CO-containing gas enriched in nickel tetracarbonyl, wherein the temperature at which nickel tetracarbonyl desorption takes place is higher than the temperature at which nickel tetracarbonyl adsorption takes place.