Synthesis of monododecylphosphate over ion exchange resin loaded by CaSO₄

Monododecylphosphate (MAP) was synthesized by esterification of phosphoric acid and lauryl alcohol over ion-exchange resin catalyst modified by metal salts. The effects of various loaded metal salts on the yield of MAP were investigated. The results showed that ion exchange resin loaded CaSO₄ exhibited good performance. The conversion of lauryl alcohol of 79.4% and the selectivity of MAP of 99.9% could be obtained, respectively after 12 hours reaction under a temperature of 90°C when the load ratio of CaSO₄ was 1.2% and the amount of catalyst equaled 3% of the total mass. The conversion of lauryl alcohol could reach 92.3% with 99.9% selectivity of MAP under the conditions above when cyclohexane was used as water removal. Catalytic performance of ion exchange resin catalyst modified by CaSO₄ remained stable after 7 times reuse.