SELECTIVE REMOVAL OF H2S FROM GASES CONTAINING H2S AND CO2 BY ABSORPTION INTO AQUEOUS-SOLUTIONS OF 2-AMINO-2-METHYL-1-PROPANOL

Selective absorption of H2S from N-2 streams containing H2S and CO2 in to aqueous solutions of 2-amino-2-methyl-1-propanol was investigated i n a 2.55 X 10(-2) m o.d. stainless steel wetted-wall column at atmosph eric pressure and constant feed gas ratio. In the range of gas flow ra tes studied (90 X 10(-6) to 180 x 10(-6) m(3)/s), the effect of gas-ph ase resistance to mass transfer on the absorption of H2S was significa nt. The rates of absorption of H2S and the selectivity factor decrease d with the increase in the contacttime. For an increase in the concent ration of the amine from 0.5 to 2.0 kmol/m(3), the rates of absorption of both CO2 and H2S increased, but to a larger extent for CO2 resulti ng in a consequent decrease in the selectivity factor. In the temperat ure range of 290.5-301.5 K the rates of absorption of CO2 increased ma rginally with the increase in temperature while the rates of absorptio n of H2S and the selectivity factor decreased. The maximum value of th e selectivity factor observed in this work was 22.5.