SEPARATION OF HYDROGEN SULFIDE FROM NATURAL GAS

摘要

A process for increasing the selectivity of an alkanolamine absorption process for selectively removing hydrogen sulfide (H2S) from a gas mixture which also contains carbon dioxide (C02) and possibly other acidic gases such as COS, HCN, CS2 and sulfur derivatives of C1 to C4 hydrocarbons, comprises contacting the gas mixture with a liquid absorbent which is a severely sterically hindered capped alkanolamine or more basic sterically hindered secondary and tertiary amine. The improvement in selectivity is achieved at the high(er) pressures, typically least about 10 bara at conditions nearing the H2S/C02 equilibrium at which C02 begins to displace absorbed hydrosulfide species from the absorbent solution.