Synthesis of TMP esters as a biolubricant from canola oil via a two‐step transesterification–transesterification process

Abstract

AbstractTrimethylolpropane esters were synthesized from canola oil by a two‐step transesterification–transesterification process. In the first step, canola oil is reacted with ethanol to produce canola oil ethyl ester, while in the second step, canola oil trimethylolpropane ester was obtained by reacting the canola oil ethyl ester and trimethylolpropane using K2CO3 as a catalyst. In the first step, under the optimal reaction conditions (70°C, 2 h, ethanol‐to‐canola oil molar ratio of 10:1, and 0.25 wt.% catalyst loading), canola oil ethyl ester was successfully synthesized with a yield of 95.7 wt.%. In the second step, the final product with the maximum total concentration of canola oil trimethylolpropane ester (82%) and the maximum conversion of canola oil ethyl ester (85%) was obtained at 130°C for 3 h with a canola oil ethyl ester to trimethylolpropane molar ratio of 3.1:1, and 1 wt.% loading of K2CO3 catalyst. The produced polyol esters can be a promising biolubricant with excellent lubricant characteristics, quenching performance, biodegradability, and rheological/tribological properties.