Eco‐friendly polyol through in situ hydroxylation from epoxidation of palm oleic acid via heterogeneous catalyst

Abstract

The world’s consumption of raw materials has shifted from the use of non-renewable materials to renewable materials. Studies on greener epoxidation by using vegetable oils to produce eco-friendly polyol have also increased. This study aims to produce polyol-based epoxidized palm oleic acid (PEPOA) with a high hydroxyl value by a novel method which is continuous hydroxylation of epoxidized palm oleic acid (EPOA) by using heterogeneous catalyst. Starting from the raw palm oleic acid, the double bonds are functionalized by introducing epoxy groups and ring-opened to produce hydroxyl groups. The best process parameters for epoxidation were optimized to maximize the oxirane value and to focus on oxirane stability. The relative conversion to oxirane (RCO) percentage was maximum (82%) after 30 mins of epoxidation reaction. Fourier transform infrared (FTIR) spectroscopy shows the absorption peak at a wavelength of 3300 cm−1, indicating the presence of hydroxyl group when polyol was analyzed. Overall, polyol with a high hydroxyl value (339 mg KOH/g), high yield (80.7%) and average molecular weight of 1045 Da was successfully produced from palm oleic acid (POA) by using continuous hydroxylation of epoxidized oleic acid. Based on hydroxyl value and average molecular weight, the polyol is deemed suitable for producing rigid polyurethane foam.