Electrochemically Assisted Biodiesel Production over a Nanoporous Benzobisthiazole-Based Sulfonated Covalent Organic Polymer at Room Temperature

Abstract

The use of solid heterogeneous catalysts for the generation of biodiesel through the esterification of fatty acids has gained considerable importance. Herein, we optimized the electrochemical synthesis of biodiesel by utilizing a heterogeneous catalyst. A benzobisthiazole-based nanoporous covalent organic polymer (BCNCOP) is synthesized and functionalized with the sulfonic group using chlorosulfonic acid to obtain sulfonated covalent organic polymer (BCNCOP-SO3H). This sulfonated porous polymer possesses a very high surface acidity with a spherical morphology. It shows excellent electrocatalytic activity toward the esterification of long-chain fatty acids, producing free acid methyl esters (FAMEs) at room temperature. The developed electrochemical synthesis utilizes an undivided cell setup with carbon paper (CP) electrodes providing an external potential of 10 V. As a result, this electrochemical approach offers an efficient, synthetic, practical protocol for biodiesel production in good yields and moderate Faradaic efficiency (FE) under ambient conditions without any challenging workup, leading to sustainability and eco-friendliness. Moreover, the electrocatalyst exhibits good stability and remains efficient for up to four consecutive cycles, suggesting its usability in various acid-catalyzed chemical reactions. � 2026 American Chemical Society