Catalytic Performance of Dicationic Ionic Liquids and ZnBr2 in the Reaction of Epichlorohydrin and Carbon Dioxide: Kinetic Study

Cyclic carbonate synthesis is an attractive route to utilize CO2 and reduce green house gas. Numbers of studies have been reported on catalytic synthesis of cyclic carbonate, however, very few studies reported on kinetic analysis of cycloaddition reaction. Present study reports a kinetic analysis for coupling reaction of epichlorohydrin (ECH) and carbon dioxide catalyzed by various dicationic ionic liquids (DILs) and zinc bromide. Effects of structural change of DILs on its catalytic activity towards cycloadditiion reaction have also been explored. In addition an attempt has also been made to discuss the plausible reaction mechanism at optimal reaction conditions for coupling of ECH and CO2. At a catalyst loading of 0.5 mmol% C-6 (mim) (mim) Br-2 and 0.25 mmol% ZnBr2, ECH conversion of 98% can be obtained at 90 A degrees C and 3 MPa in 40 min. Maximum conversion efficiency (98%) and minimum activation energy (20 kJ/mol) was associated with catalytic system comprising of C-6 (mim) (mim) Br-2 and ZnBr2. Thus, from industrial application point of view C-6 (mim) (mim) Br-2 and ZnBr2 are potential catalysts for cyclic carbonate synthesis. [GRAPHICS] .