Zn2(C9H3O6)(C4H5N2)(C4H6N2)3 MOF as a highly efficient catalyst for chemical fixation of CO2 into cyclic carbonates and kinetic studies

Abstract

Zn2(C9H3O6)(C4H5N2)(C4H6N2)3 (Zn-BTC-2MeIm) was hydrothermally synthesized and employed as a highly efficient catalyst for CO2 coupling with epichlorohydrin (ECH). Various techniques such as XRD, FT-IR, XPS, TG-DTG, NH3/CO2-TPD were employed for characterizing the compound. Interestingly, TG profile illustrated the Zn-BTC-2MeIm was stable above 200°C. The highest catalytic activity of 98.93% conversion of ECH and 98.32% selectivity to chloropropene carbonate was observed under the optimum conditions (100°C, 120mesh, 1000rpm, 3.0MPa, 6h, 0.75wt.% of ECH). Besides, the recyclability results exhibited Zn-BTC-2MeIm compound could be reused no less than three times with a slight reduction in its catalytic ability. Moreover, coupling results of CO2 with other epoxides showed this compound could efficiently convert various epoxides into cyclic carbonates. Finally, the investigation of the kinetic exhibited the law of CO2 coupling with ECH was coincident with the first order kinetic and the activation energy (Ea) was to be 113.38kJ/mol.