UOP, Chevron use ionic liquids in refineries

HONEYWELL UOP and Chevron have introduced a process to use an ionic liquid instead of hydrofluoric or sulphuric acids in the alkylation step of refining to produce high-octane fuel.

More than half of the world’s 700 refineries currently use the highly-corrosive acids as the catalyst in the alkylation step, a process developed by UOP and introduced in 1938. The new ISOALKY technology, developed by Chevron and licensed by UOP, will be the first successful liquid alkylation technology to be introduced since then. Higher octane fuel additives ensure that fuel burns more clearly and lowers its environmental impact.

For the past five years, Chevron has successfully tested the ionic liquids alkylation step at its Salt Lake City refinery in the US. It has now committed to converting the hydrofluoric acid alkylation unit at the refinery to use ISOALKY technology. Work will begin in 2017, with the technology becoming fully operational in 2020. As a result, all of the refinery’s hydrofluoric acid handling equipment and the dangerous acid itself will be removed from site.

ISOALKY technology uses an ionic liquid at temperatures below 100?C to produce a high octane blending component from the stream from a catalytic cracker. Ionic liquids are much less volatile than conventional acids but still have strong acid properties and can perform acid catalysis reactions. The new process requires less catalyst volume to produce the same amount of octane. In addition, the catalyst can be regenerated on site, lowering the environmental footprint.

“Ionic liquids alkylation offers a compelling economic solution compared to conventional liquid acid technologies while delivering the same yields and high levels of octane. This is a revolutionary new technology for refiners to produce alkylate and improve the quality of their gasoline pool,” said Mike Millard, vice president and general manager of Honeywell UOP’s Process Technology and Equipment business.