Patent ID: 8123946

Claim:
A method for removal of metal sulphide particles and dissolved contaminants from a liquid stream obtained by the steps of (i) contacting a gas stream comprising hydrogen sulphide and metal carbonyls with a solvent, thereby obtaining a solvent enriched in hydrogen sulphide and in metal carbonyls; and (ii) heating and depressurising the solvent enriched in hydrogen sulphide and metal carbonyls in a solvent regenerator, thereby converting at least part of the metal carbonyls to metal sulphide particles, to obtain the liquid stream comprising solvent and metal sulphide particles and dissolved contaminants; said metal sulphide particle and dissolved contaminant removal method comprising the steps of: withdrawing a liquid stream comprising solvent, metal sulphide particles and dissolved contaminants from said solvent regenerator; dividing said liquid stream into two parts; using the first part of said liquid stream to remove further amounts of metal carbonyls and hydrogen sulphides from a gas stream comprising these compounds; contacting the second part of said liquid stream with a filter system comprising a porous membrane having a crosslinked structure and a pore size less than 0.1 micron, said porous membrane allowing a flux of at least 1200 kg/m 2 /day, thereby transferring metal sulphide particles from said liquid stream onto the membrane surface to obtain a liquid stream depleted of metal sulphide particles and a filter system comprising a membrane enriched in metal sulphide particles; passing said liquid stream depleted of metal sulphides to a separation column wherein water and other dissolved contaminants in said liquid stream are separated from the solvent in said liquid stream; and using the said solvent from said separation column to remove metal carbonyls and hydrogen sulphide from gas streams containing these compounds.