Absorbent for selective removal of hydrogen sulfide from a fluid stream

US10464013B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Gerald Vorberg · Ludwigshafen, DE
• Ralf Notz · Ludwigshafen, DE
• Thomas Ingram · Keller, US
• Georg Sieder · Bad Dürkheim, DE
• Torsten Katz · Ludwigshafen am Rhein, DE

Key dates

• Filing date: Aug 20, 2015
• Grant date: Nov 5, 2019
• Expiry date: Sep 12, 2035

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C10L2290/545
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

An absorbent for selective removal of hydrogen sulfide from a fluid stream comprises an aqueous solution of a) a tertiary amine, b) a sterically hindered secondary amine of the general formula (I) in which R1 and R2 are each independently selected from C1-4-alkyl and C1-4-hydroxyalkyl; R3, R4, R5 and R6 are each independently selected from hydrogen, C1-4-alkyl and C1-4-hydroxyalkyl, with the proviso that at least one R4 and/or R5 radical on the carbon atom bonded directly to the nitrogen atom is C1-4-alkyl or C1-4-hydroxyalkyl when R3 is hydrogen; x and y are integers from 2 to 4 and z is an integer from 1 to 4; where the molar ratio of b) to a) is in the range from 0.05 to 1.0, and c) an acid in an amount, calculated as neutralization equivalent relative to the protonatable nitrogen atoms in a) and b), of 0.05 to 15.0%. One preferred amine of the formula I is 2-(2-tert-butylaminoethoxy)ethanol. The absorbent allows a defined H2S selectivity to be set at pressures of the kind typical in natural gas processing.