Process for recovery of sulfur from sour/natural gas using biodegradable carboxylic acid metal chelates

摘要

A process for recovery of sulfur from sour/natural gas stream containing H2S is described. It involves contacting the stream with an aqueous solution of biodegradable water soluble carboxylic acid metal chelate. This carboxylic acid metal chelate contains an oxidizing polyvalent metal e.g. Fe (III) and one of the acid from gluconic acid, malic acid, citric acid, succinic acid, oxalic acid. The hydrogen sulfide gas is reduced to hydrogen and elemental sulfur, which is recovered as precipitate. The iron in the metal chelate is reduced in the process and can be regenerated by oxidation.