Methoxylation of methyl oleate in the presence of dealuminated Y faujasites in their protonic form

Methoxylation of methyl oleate into methyl methoxy stearate was carried out in a batch reactor at temperatures ranging from 150 to 190°C in the presence of dealuminated H-Y faujasites as catalysts. In the presence of an excess of methanol, the H-Y faujasite with a Si/Al ratio of 15 was shown to achieve the title reaction with a yield of methyl methoxy stearate that does not exceed 40% because of the parallel formation, at comparable rates, of methyl oleate isomers identified as methyl elaidate, methyl trans-vaccenate, and methyl cis-vaccenate. Isomerization reactions were confirmed to occur rapidly in an independent manner. FFA are also present in small amounts owing to the in situ dehydration of methanol and subsequent hydrolysis of the esters. Finally, starting from pure oleic acid leads to results similar to those obtained with methyl oleate as the starting material.