Mesoporous (Ta, Nb)3W7 Modified with Stearic Acid Used as Solid Acids for Esterification

Mesoporous solid acids Ta3W7 and Nb3W7 were prepared from TaCl5 and NbCl5 with WCl6 in the presence of stearic acid (SA) via a sol-gel method, respectively. For comparison, mesoporous Ta3W7-P123 mixed oxides and mesoporous Nb3W7-P123 mixed oxides were synthesized in the same way. The catalysts were characterized through TGA, XRD, SEM, TEM, BET, and NH3-TPD. Experimental results showed that Ta3W7-SA and Nb3W7-SA exhibited several advantages such as higher activity, shorter preparation period, lower cost, stronger acid sites, and higher surface area, which had potential to be used as mesoporous heterogeneous catalysts in biodiesel production.

Enhanced base-catalyzed activity and structural stability of nitrogen-doped carbon modified MgO–MgFe2O4 magnetic composites as catalysts for transesterification of tributyrin

Magnetic nitrogen-doped carbon modified MgO–MgFe₂O₄ catalysts exhibited greatly enhanced base-catalyzed activity and structural stability.

Esterification of fatty acids from waste cooking oil to biodiesel over a sulfonated resin/PVA composite

PVA enhances the catalytic activity and reusability of s-CER/PVA for esterification by absorbing the water produced and liberating reactive –SO₃H sites.

An investigation on the catalytic capacity of dolomite in transesterification and the calculation of kinetic parameters

The catalytic capacity of dolomite in transesterification was investigated and the kinetic parameters were calculated. The activated dolomites as transesterification catalyst were characterized by X-ray diffraction, nitrogen adsorption and desorption and Hammett indicator method, where the original dolomite was analyzed by thermogravimetric and X-ray fluorescence in advance. Its potential catalytic capacity was validated from aspects of the activated temperature and the reused property, where the reliability of the experimental system was also examined. Then, influences of the catalyst added amount, the mole ratio of methanol to oil, the transesterification temperature and the transesterification time on the catalytic capacity were investigated. Finally, kinetic parameters of the transesterification catalyzed by the activated dolomite were calculated.