Experimental optimization during epoxidation of a high-oleic palm oil using a simplex algorithm

Abstract

This work explored the epoxidation of high oleic palm oil (HOPO) extracted from recently developed palm tree hybrids. The process was carried out by reaction with 50 % wt·H2O2 using peracetic acid generated in-situ as oxygen carrier, and H2SO4 as catalyst. The study focused on the optimization of the operating conditions to maximize the productivity of oxirane groups in the epoxidized oil, considering the conversion of unsaturated groups and the selectivity to oxirane ring. The optimization was done by experimental application of a simplex algorithm varying reaction temperature (55–70 °C), catalyst loading (1–5 % wt.), mol ratio of H2O2 to HOPO unsaturations (1−10), acetic acid loading with respect to HOPO (2–10 % wt.), and reaction time (1–6 h). Optimal conditions were obtained after eight experimental steps, reaching a conversion of oil’s unsaturations of nearly 90 %, with a selectivity towards oxirane groups of 88.6 %. The obtained oil had an oxygen oxirane content of 3.48 %wt., which corresponded to ~80 % of theoretical yield. The optimal conditions were tested in a subsequent kinetic experiment, and the results were reproduced obtaining an epoxy number of 3.5 and a yield of 79.7 %. This methodology can also be used to assess novel epoxidation catalysts.