| abstract |
Acidic gases are substantially removed from a normally gaseous mixture by a process comprising contacting the normally gaseous mixture with an amine-solvent liquid absorbent comprising (i) an amine mixture comprised of at least about 50 mol % of a sterically hindered amine and at least about 10 mol % of a tertiary amino alcohol, wherein said sterically hindered amine contains at least one secondary amino group which is part of a ring and is attached to either a secondary or tertiary carbon atom or a primary amino group attached to a tertiary carbon atom, and (ii) a solvent for said amine mixture which is also a physical absorbent for said acidic gases. The liquid absorbent may also include up to about 35 weight percent water. The coaction of the sterically hindered amine and the tertiary amino alcohol in conjunction with the solvent provides an increase in the amount of CO2 containing acidic gases absorbed compared to the use of the same sterically hindered amines alone and lowers the heat of reaction. |