Sodium stannate promoted double bond cleavage of oleic acid by hydrogen peroxide over a heterogeneous WO3 catalyst

Abstract

The production of valuable mono- and dicarboxylic acids from abundant and renewable vegetable oil sources is of great industrial interest. It is demonstrated by a simple and eco-friendly heterogeneous catalytic system for direct oleic acid (OA) cleavage by hydrogen peroxide to produce azelaic acid (AA) and nonanoic acid (NA). Commercially available tungsten oxide was used as a heterogeneous catalyst without any modification or pretreatment, and sodium stannate was used as a H₂O₂ stabilizer to improve the efficiency of the oxidant. The sodium stannate additive notably improved the product yields and it could be recycled together with the tungsten oxide catalyst. Isolated product yields up to 89% for azelaic acid and 65% for nonanoic acid were achieved from oleic acid in this simple system, which should be among the best results for oleic acid cleavage in heterogeneous systems. This strategy is also applicable for other catalytic systems for the cleavage of OA or its derivatives. This work provides a potential method for the large scale upgrading of oleic acid.