Study Of Synthesis Technology For Acetyl Trioctyl Citrate

Citric acid ester is a kind of avirulent insipidity, plasticizing efficiency, green environmental protection plasticizer, and citric acid ester of relatively high molecular weight volatile smaller, more resistance to low temperature, soap water, wider application fields. At present, the research on synthesis and application of such plasticizer is less in the domestic. In this paper, with p-toluene sulfonic acid as catalyst, trioctyl citrate (TOC) and acetyl trioctyl citrate (ATOC) of high molecular weight were synthesized from citric acid,octyl alcohol, acetic anhydride.and their synthesis processes were optimized.The orthogonal experiment and single factor optimization were used to determine influence of various factors such as raw material ratio, catalyst dosage, reaction temperature and reaction time on the reaction result. The optimum synthetic conditions of trioctyl citrate with citric acid, octyl alcohol as raw material:the amount of substance ratio on citric acid and octyl alcohol was1:4.0, the dosage of catalyst was1.5%of the mass of citric acid, the reaction temperature was120～180℃, reaction time was2.0h, under this condition, the esterification rate could reach98.50%. The optimum synthetic conditions of acetyl trioctyl citrate with trioctyl citrate,acetic anhydride as raw material:the amount of substance ratio on trioctyl citrate and acetic anhydride was1:1.5, the dosage of catalyst was1.5%of the mass of trioctyl citrate. reaction temperature was90℃, reaction time was1.75h, under this condition, the yield could reach97.30%.TOC which was not alkaline cleaned, washed, dried, decolored was directly used for acetylation reaction,this was discussed in the experiment. the results showed that only adding a small amount of catalyst, without changing the raw material ratio, reaction temperature, reaction time,the yield of acetyl trioctyl citrate still reach97.30%,.The results of the study provided reliable basic data on the industrial production of trioctyl citrate and acetyl trioctyl citrate.it has a good prospect of industrial application.