Esterification of tall oil fatty acid catalyzed by Zr4+-CER in fixed bed membrane reactor

In this study, Zr 4+ -CER was used as a solid acid catalyst to catalyze the esterification reaction. The esterification of tall oil fatty acids (TOFA) with ethanol dehydration was studied by fixed-bed coupled pervaporation (PV). The Zr 4+ -CER catalyst was characterized in detail by Py-IR, NH 3 -TPD, BET, IEC , ICP-OES, SEM, and FTIR. The effects of ethanol/oil molar ratio , catalytic bed height, reaction temperature and feed rate on TOFA conversion were investigated. The esterification reaction conditions were optimized by orthogonal test, and the optimal conditions were ethanol/oil molar ratio 15:1, catalytic bed height 120 mm, reaction temperature 80 °C, and feed rate 0.3 ml/min. The TOFA conversion rate was 99.51 %. After six esterification cycles, the TOFA conversion of the catalyst reached 90.03 %, indicating that the catalyst had high stability. The esterification process using Zr 4+ -CER as the catalyst follows the second-order kinetic model , with an activation energy of 39.54 kJ/mol. Furthermore, the economic analysis of biodiesel production indicates that the Zr 4+ -CER catalyst has the potential to decrease production expenses, presenting an encouraging prospect for future biodiesel industrialization.