SULFOLANE (Tetrahydrothiophene 1.1 Dioxide)
SULFOLANE is a clear, colourles liquid and used in the gas treating process (sulfinol make-up) for purifying acidic (or sour) gas stream i.e. the removal of compounds such as hydrogen sulphide, carbon dioxide, carbon oxysulphide, carbon disulphide and mercaptan in Liquid Natural Gas (LNG) plants.
Shortly after the Sulfinol process was implemented, Sulfolane was found to be highly effective in separating high purity aromatic compounds from hydrocarbon mixtures using liquid-liquid extraction. This process is still widely used today in refineries and the petrochemical industry.
Because Sulfolane is one of the most efficient industrial solvents for purifying aromatics, the process operates at a relatively low solvent-to-feed ratio, making Sulfolane relatively cost effective compared to similar-purpose solvents. In addition, it is selective in a range that complements distillation, where Sulfolane cannot separate two compunds, distilillation easily can and vice versa, keeping Sulfolane units useful for a wide range of compounds with minimal additional cost.