High-yielding synthesis of alkyl stearates from stearic acid within a closed batch reactor using heteropolyacids as efficient and recyclable catalyst

Abstract

This study reports high-yielding and scalable synthesis of alkyl stearates from stearic acid (SA) within a closed batch reactor using commercially-available heteropolyacid catalysts. The reaction was carried out by using different commercially-available heteropolyacids and reaction conditions were optimized by using phosphotungstic acid (PTA) catalyst. The solvent-free, gram-scale reactions afforded alkyl stearates in excellent isolated yields (>95%) within 4 h at 110 °C using slight excess of alcohols and only 1 mol% of the phosphotungstic acid (PTA) catalyst. The PTA catalyst was successfully recovered and reused for five consecutive cycles without significant loss in mass or activity.