Novel System for Solid Catalyzed Isobutane/Olefin Alkylation

Isobutene/olefin alkylation is a major refinery process in which light hydrocarbons (isobutene and, mainly, C3 and C4 olefins) are converted to a high octane gasoline feedstock. Alkylate currently accounts for a key fraction of the total U.S. gasoline pool; in fact, concerns over emissions have led to an interest in increasing the amount of alkylate used in gasoline. However, environmental and safety concerns present a barrier to this increase, as current processes for alkylate production employ hazardous liquid acids. As yet, a practical process based on solid catalysts has not been identified ¿ conventional fixed bed processes have faced rapid catalyst aging and downtime for regeneration. This project will develop a novel reactor approach to solid-catalyzed isobutene/olefin alkylation in which olefin polymerization at the catalytic surface is limited, thereby avoiding the primary issue with solid catalyzed alkylation. Moreover, the proposed approach offers the potential for higher quality alkylate. Phase I demonstrated the validity of the system to limit olefin polymerization, produced high quality alkylate via the reaction of isobutene with 2-butene, defined the basic parameters of the system (including coatings, reactor configuration and operating conditions), and documented stable operation over a 100-hour test run. In collaboration with a major petroleum refiner, Phase II will optimize the reactor configuration (geometry and catalyst selection) and operating conditions (feed rates/ratio, system temperature, and system pressure), and demonstrate long-term life (high productivity of high octane product for 1000+ hours of continuous operation). Commercial Applications and Other Benefits as by the awardee: The replacement of liquid-acid-based HF and sulfuric acid processes with solid catalyst process should improve yield, eliminate environmental and safety complications, simplify plant design (e.g., by avoiding acids handling and refrigeration steps), reduce capital costs, and reduce energy consumption and operating costs.