Immobilization of thiol-functionalized ionic liquids onto the surface of MIL-101(Cr) frameworks by S[sbnd]Cr coordination bond for biodiesel production

Abstract

A novel functionalized MOF heterogeneous catalyst (MIL-101(Cr) @MBIAILs), 2-Mercaptobenzimidazole ILs with electron-rich SH groups immobilized onto the surface of the well-defined MIL-101(Cr) frameworks, was constructed and fabricated by the SCr coordination bond on the basis of the facile post-synthetic modification strategy. The heterogeneous catalyst was measured by XRD, FTIR, SEM, TEM, TGA, EA and N2 adsorption–desorption, and the catalytic behavior of the catalyst was assessed by the esterification about oleic acid and methanol as a model reaction. The results showed that MBIAILs have been successfully immobilized onto the surface of MIL-101(Cr) frameworks by SCr coordinate bonds. More importantly, the conversion of oleic acid just decreased from 91.0% to 82.1% when the catalyst had been reused six times. This exhibited the prepared catalyst had superior catalytic behavior and excellent reusability.