无羧酸条件下清洁合成环氧大豆油

在无羧酸条件下,以乙酸乙酯为溶剂、甲基三辛基硫酸氢铵为相转移催化剂,用30%(质量分数)过氧化氢溶液直接环氧化大豆油合成了环氧大豆油。通过核磁共振氢谱及碳谱、傅里叶变换红外光谱、黏度测定等方法对产物的结构进行了表征与分析,并根据国家标准的方法对产物的色泽、酸值、环氧值和碘值进行了测定。同时考察了反应时间、反应温度及溶液pH对产物环氧值的影响,通过正交实验优选了反应条件。实验结果表明,无羧酸条件下,以过氧化氢为氧化剂可以成功地实现大豆油的环氧化,在溶液pH为2、反应温度60℃、反应时间7h的条件下,产物的环氧值为6.27%,碘值(100g)为5.80g。此方法避免了反应中生成过酸,副产物生成量减少,提高了产品质量。

Clean Synthesis of Epoxidized Soybean Oil Without Carboxylic Acid

Epoxidized soybean oil(ESBO)was synthesized by reaction of soybean oil(SBO)with hydrogen peroxide using methyltri-n-octylammonium hydrogen sulfate as phase transfer catalyst and ethyl acetate as solvent.The synthesis was an efficient and environmentally friendly process without traditionally used carboxylic acid as catalyst.Structure of synthesized ESBO was characterized by means of ~1H NMR,~(13)C NMR,and FTIR.Acid value,epoxy value and iodine value of product conformed to China national standard(CNS).Effects of reaction time,temperature and pH on epoxidation were studied by orthogonal experiment.Under optimal conditions:pH 2,reaction temperature 60℃ and reaction time 7h,epoxy value and iodine value(100g)of product could reach(6.27%) and 5.80g,respectively.Epoxidized soybean oil was successfully synthesized.The process featured by avoiding and decreasing unfavorable byproduct,and improved quality of product.