Coconut shell activated carbon tethered ionic liquids for continuous cycloaddition of CO2 to epichlorohydrin in packed bed reactor

Various ionic liquids (ILs) were in situ prepared on coconut shell activated carbon (CSAC) granules. Cycloaddition of CO2 to epichlorohydrin (ECH) was continuously carried out in a packed-bed reactor without using solvent or cocatalyst. The conversion rates of ECH over the CSAC tethered Bmim/Br, Bmim/BF4, Bmim-OH/Br and Bmim-COOH/Br were 63.4%, 74.5%, 83.4% and 85.9% at 140 °C and 1.4 MPa, respectively. The selectivities to epichlorohydrin carbonate (ECHC) were over 98% for the four catalysts. The ECH conversion stabilized at 82% for the CSAC tethered Bmim-COOH/Br after 50 h of continuous performance in the packed bed reactor.