Initial studies on hydroxylation of unsaturated palm fatty acids were carried out with very promising results. Hydroxylation of unsaturated palm fatty acids with hydrogen peroxide-acetic acid for two hours gave products with melting points of 79°C – 128°C, acid values of 135-165, saponifiable values of 119-128 and hydroxyl values of 384-440. Yield of the product was about 80% – 90%. The product characteristics were very different from those obtained from other oils. For example, hydroxy fatty acid from sunflower oil has a saponifiable value of 212, acid value of 140 and hydroxyl value of 222 (Dahlke et al., 1995).

The product obtained in this study was not only 9,10-dihydroxystearic acid but also some fatty acids and 10-oxo-stearic acid. By adding hydroxystearic acid at a concentration of 0.2%, the life of steel was extended by up to 10 times, showing that hydroxystearic acid was very effective as a rust inhibitor. Therefore, hydroxylation of unsaturated palm fatty acid is a promissing process for obtaining hydroxystearic compounds.