Intensification of isobutane/1-butene alkylation process in a micromixing microreactor catalyzed by ILs/H2SO4

The products of isobutane/butene alkylation are ideal high-octane blending components of gasoline pool. Binary mixtures of acidic imidazolium ionic liquids [CnMIm][OTf] (n = 4, 6, 8) and H2SO4 were used to catalyze isobutane/butane alkylation in a microreactor integrated with staggered herringbone grooves. The mixing be-haviors of acid and hydrocarbons were simulated in the microchannel configured with micromixing elements by computational fluid dynamics (CFD) simulation. [CnMIm][OTf]/H2SO4 showed better catalytic performance than H2SO4 solely. Especially the [OMIm][OTf]/H2SO4 showed excellent performance. In the designed micro-reactor, the alkylate with research octane number (RON) of 99.5 was obtained at 10.0C and reaction time of 81 s with [OMIm][OTf]/H2SO4 as catalyst. The results are better than currently available research works imple-mented in batch reactors. The catalyst [OMIm][OTf]/H2SO4 was recycled 14 times without reducing the cata-lytic activity. It indicates that the composite catalysts possess excellent reutilization performance.

Automated summary

The products of isobutane/butene alkylation are ideal high-octane blending components of gasoline pool. The use of binary mixtures of acidic imidazolium ionic liquids and H2SO4 as catalysts showed better catalytic performance, especially [OMIm][OTf]/H2SO4 which demonstrated excellent performance and reutilization capability.