Aminopyridine derivatives for removal of hydrogen sulfide from a gas mixture

Abstract

The present invention relates to a novel class of aminopyridine derivatives with the general formula: wherein R; R, R, and Rare each independently hydrogen, an alkyl group, —(O—CH—CH2)-OH wherein n is an integer from 0 to 8, —CH—(O—CH—CH)n-OH wherein n is an integer from 0 to 8, an hydroxyalkyl group, an aminoalkyl group where the nitrogen can be part of a 5 or 6 ring membered cycle, an alkylene group containing quaternary ammonium, a carboxylic acid and/or a salt thereof, or a sulphonic acid and/or a salt thereof, preferably R; R, R, and Rare each hydrogen. The compounds are useful for removal of hydrogen sulfide and other impurities from fluid streams containing hydrogen sulfide, including selective removal from such streams which also contain carbon dioxide. Examples of the fluid stream include a gas stream, for example natural gas, synthesis gas, tail gas, refinery gas, or from liquid streams such as liquid or liquefied hydrocarbons, for example Liquefied Petroleum Gas or Natural Gas Liquids.