Present technologies for hydrogen sulfide removal from gaseous mixtures

Natural gas, refinery gas, and coal gas contain acid gases such as hydrogen sulfide (H 2 S) and carbon dioxide that must be removed from the gas stream due to the toxicity of H 2 S and to prevent corrosion to piping and production facility caused by the acid gases. In this article, current technologies for the acid gas removal are selected and reviewed. The review includes absorption, adsorption, conversion of H 2 S into elemental sulfur, and membrane reactor for H 2 S decomposition and desulfurization. Recently, hollow fiber membrane contactor has been in the limelight of research in H 2 S absorption from gaseous mixture due to its potential to overcome problems such as foaming and loading. Recent trends on Claus tail gas cleanup technologies are highlighted due to the recent progress in membrane technology. The article also suggests current research on the acid gas removal technology using catalytic membrane reactor. The interest on finding suitable active component and support and studying the membrane structure for enhanced removal of acid gases is likely to be rekindled in the near future.