Patent ID: 7097671

Claim:
A method of removing colloidal metal sulfides formed from metal carbonyls from a methanol scrubbing solution used to scrub industrial gas at a low temperature, the method comprising the steps of: (a) introducing said methanol scrubbing solution containing colloidal metal sulfides formed from metal carbonyls into a precipitation vessel; (b) heating the methanol scrubbing solution containing colloidal metal sulfide particles in said precipitation vessel to cause growth of the metal sulfide particles therein; (c) introducing the methanol scrubbing solution containing metal sulfides from said precipitation vessel into a methanol/water separation column in which: a rising stream of methanol vapor is passed in counterflow to a descending stream of water, a head product rich in methanol is removed from said separation column for scrubbing of industrial gas, and a sump product rich in water is removed from said separation column; and (d) removing from the sump product metal sulfides from said separation column in the form of larger particles than the particles of the colloidal metal sulfides introduced according to step (a).