Characteristics of Absorbent Loss and CO₂-Selective Absorption of CO₂/SO₂ Gas into Aqueous 2-Amino-2-methyl-1-propanol/Ammonia Solution

Abstract

The effect of SO 2 on the loss of 2-amino-2-methyl-1-propanol (AMP)/ammonia (NH 3 ) solution and simultaneous removal of CO 2 and SO 2 into aqueous AMP/NH 3 solution was investigated. Solvent loss and selectivity of CO 2 were studied using a reactor constructed of stainless steel and a wetted wall column. The losses of NH 3 from solution containing 1 wt % NH 3, 30 wt % AMP + 1 wt % NH 3, and 30 wt % AMP + 1 wt % NH 3 loaded with 0.5 mol of CO 2 /mol at 313 K were 0.0179, 0.013, and 0.010, respectively. The initial degradation rate constants for the CO 2 /SO 2 -loaded AMP solution were 0.000 21–0.003 186 h –1, higher than those for the CO 2 -loaded solution of 0.000 9–0.000 95 h –1 . Selective absorption of CO 2 into aqueous AMP/NH 3 solution decreased from 0.99 to 1.48 as a function of SO 2 partial pressure (1, 3, 5, 10, and 15 kPa).