(65d) Solid Acid Catalyzed Alkylation of Isobutane with Light Olefins

Alkylate is an ideal gasoline blending component because of its high octane number, low vapor pressure and absence of sulfur and aromatic compounds. Over the last six decades, production of high-octane alkylate via alkylation of isobutane with light olefins has relied on hazardous liquid acid (HF or H2SO4) catalysts, which pose safety risks and have caused unfortunate refinery accidents. Although solid acid catalysts (SACs) have been explored for nearly four decades as safer alternatives, they deactivate rapidly and have largely been economically unattractive when compared to liquid-acid catalyzed alkylation. Over the past decade, Exelus has designed a new solid-acid catalyst  -ExSact - with significantly higher stability, which makes solid acid alkylation finally competitive with conventional liquid acid technologies. The unique design of the ExSact catalyst allows a wide variety of feedstocks to be processed while maintaining high overall product quality and yield. A simple regeneration scheme using hydrogen allows the design of a dual fixed bed process. The viability of this approach has been ascertained through 1000+ hour testing using refinery feedstocks. In this talk, the development of this process will be described, placing it in the context of other recent studies.