Preparation and catalytic performance of N-[(2-Hydroxy-3-trimethylammonium) propyl] chitosan chloride /Na2SiO3 polymer-based catalyst for biodiesel production

A novel polymer-based alkaline catalyst was prepared with sodium silicate (Na₂SiO₃) and N-(2-Hydroxy-3-trimethylammonium) propyl] chitosan chloride (HTCC), interlinked by epichlorohydrin (ECH), for biodiesel production. The structure and properties of the catalyst were studied by Fourier transform infrared spectroscopy, thermogravimetry-mass spectrometry and transmission electron microscopy. The effects of the variables on the transesterificaton of soybean oil to biodiesel were investigated. It is found that Na₂SiO₃ was bridged on HTCC chains through ECH and well dispersed in HTCC matrix in nano size. The transesterification conversion reached at 97.0% under the reaction conditions of methanol/oil molar ratio of 6:1, catalyst loading of 4.0 wt.% at 55 °C for 60 min. After the second run, the catalytic activity kept stable, which was contributed to the stability and dispersion of Na₂SiO₃ in the catalyst.