Transesterification of glycerol trioleate catalyzed by basic ionic liquids immobilized on magnetic nanoparticles: Influence of pore diffusion effect

Abstract

Supported ionic liquids have become a hotspot in heterogeneous catalysis. 1-Allyl-dodecylimidazolium hydroxide ([ADIm][OH]) basic ionic liquids immobilized on magnetic mesoporous SiO2/CoFe2O4 nanoparticles (SCF) and magnetic CoFe2O4 nanoparticles (CF) were prepared and characterized via FTIR, XRD, TEM, TG–DTA, VSM, elemental analysis and N2 adsorption–desorption measurements. Catalytic performance of both supported ionic liquids catalysts (SILCs) was evaluated through transesterification of glycerol trioleate. The SCF carrier consisted of mesoporous silica matrix and uniformly dispersed CoFe2O4 nanoparticles, while CF carriers were nanosized CoFe2O4 particles with an average size of 15nm. All of the carriers and the supported catalysts showed excellent paramagnetism. The two SILCs showed excellent catalytic activities higher than NaOH. Furthermore, the structure of the carriers had important influence on the catalytic performance of SILCs. Compared with the two SILCs, [ADIm][OH]/SCF presented a lower catalytic activity at the beginning of the reaction but higher catalytic activity when reaction time was long enough than [ADIm][OH]/CF due to the pore diffusion effect.