Role of aromatics in isobutane alkylation of chloroaluminate ionic liquids: Insights from aromatic − ion interaction

•The effect and interaction of aromatics on the CIL alkylation were analyzed.•Adding aromatics can prolong AlCl4− lifetime and improve the product selectivity.•Aromatic-AlCl4− and [aromatic H]+ contribute to the inhibition of side reactions.•Enrichment of aromatics at the interface is conducive to improving the alkylation performance.