Tunable Microwave Flow System for Scalable Synthesis of Alkyl Imidazolium-type Ionic Liquids

A continuous flow auto-frequency tuning single-mode microwave reactor is disclosed as a powerful platform to synthesize alkyl imidazolium salts as ionic liquids/ionic liquid precursors in up to near-quantitative yields, 100-600 g h(-1) productivities and record space-time yields. Challenges faced, including viscosity changes, dielectric property changes, and phase separations, were addressed by different operation modes of the reactor without reactor redesigning. Depending on the purpose, this highly productive method could prove to be useful for intensive applications of ionic liquids.

Automated summary

A continuous flow auto-frequency tuning single-mode microwave reactor is presented as a powerful platform for synthesizing alkyl imidazolium salts as ionic liquids/ionic liquid precursors. The reactor achieves near-quantitative yields, high productivities, and record space-time yields, and addresses challenges such as viscosity changes, dielectric property changes, and phase separations.