PSS sorbents for removing trace hydrogen sulfide in methane

Abstract

Sorbents of the pressure swing sorption process (PSS) to remove trace amount of H2S (190 ppm) contained in methane were experimentally studied. The sorbents consist of adsorbent carrier (silica gel or activated carbon) and absorbent which spreads outside the carrier granules’ pores (triethanolamine, TEA or N-methyl-2-pyrrolidone, NMP). The results of breakthrough and regeneration tests show that silica gel is more suitable to be the carrier than activated carbon and TEA is more suitable to be the absorbent than NMP. The loaded absorbent could enlarge the sorption capacity of H2S considerably. And the BET tests indicate that the absorbent deposits on the surface of the carrier’s pores and can reduce the mesopores’ size and block the micropores.