Hydrate-based Capture of Acidic Gases for Clean Fuels with New Synergic Additives

Abstract

Abstract The widespread need for the removal of carbon dioxide (CO 2 ) and hydrogen sulfide (H 2 S) from process gas streams associated with hydrogen synthesis plants, upgrading of natural gas, landfill gas recovery, and enhanced oil recovery has led to a continuing interest in developing acid gas separation technologies. This work experimental investigated the hydrate formation processes for capturing acidic gases (CO 2 and H 2 S) from mixture gas (biogas and natural gas) with a new synergic additive, which is composed physical gas solvent (TMS) and traditional hydrate promoter (TBAB). Based on the thermodynamic and kinetic studies, the results show that the hydrate formation process with the synergic additives can capture CO 2 and H 2 S synchronously. The synergic additives not only can considerably moderate the equilibrium hydrate formation conditions, but also make high selectivity of CO 2 and H 2 S over CH 4 during the hydrate formation process, and improve the formation rate and gas storage capacity through their excellent promote effect on the solubility and diffusivity of acidic gases. It will be of practical interest in relation to the fundamental study of enhancing gas hydrate formation and of potential importance for the industry application of gas hydrate.