On continuous, solvent-free synthesis of ionic liquid [BMIM]Br in a microbore tube

Abstract

Synthesis of an imidazolium-based ionic liquid (IL) 1-butyl-3-methylimidazolium bromide, a precursor to hydrophobic ILs having potential applications in nuclear fuel cycle, is carried out in a microbore tube in solvent-free and continuous mode. Product yield increased monotonically with increasing reaction temperature and residence time. Space–time–yield (STY) and production rate decreased with increase in residence time and increased with increase in reaction temperature. Maximum values of STY and production rate achieved are 131.5 g/min l and 278 g/day, respectively. Experimental data suggest that the reaction, when carried out in a microbore tube, is kinetically controlled. Flow patterns inside the microbore tube, observed using a high speed imaging system, also suggest the same.