(165e) Ultrasound-Assisted Oxidative Desulfurization of Natural Gasoline

Natural gasoline is an important blend stock for on-road gasoline. However, its sulfur content is typically above the mandated limit for on-road gasoline (30 ppm S) which limits the extent to which natural gasoline can be blended. SulphCo® has developed a simple, cost-effective, scalable and environmentally-benign process to desulfurize natural gasoline, using an ultrasound-assisted oxidative approach. Sulfidic species in natural gasoline are oxidized in a continuous process using hydrogen peroxide, a homogenous catalyst and exposure to a high-power ultrasound probe that creates an intense cavitation field in the process fluid. The resulting oxidized sulfur species, such as sulfones, sulfoxides, and sulfonic acids, are water-soluble and are removed with a simple water-wash step. Three natural gasolines from different sources, ranging from 52 ppm to 379 ppm S, were desulfurized to levels below 30 ppm S. Total process operating expenses to achieve these reductions were significantly below those of competing technologies.