超声条件下硫酸催化制备环氧大豆油的研究

PREPARATION OF EPOXIDIZED SOYBEAN OIL CATALYZED BY SULFURIC ACID UNDER ULTRASONIC CONDITIONS

以甲酸为活性氧载体,以硫酸为催化剂,在超声条件下对大豆油进行环氧化.考察了硫酸用量、甲酸和双氧水的物质的量比、超声频率、功率、温度、时间等因素对大豆油环氧值的影响,确定最佳工艺条件为:硫酸用量为2.0%(W/W),甲酸用量为20%(W/W),n(双氧水)∶n(甲酸)=7.76∶1,超声频率为100 kHz、功率为120 W、温度为65℃、超声时间为45 min.在此条件下得到的大豆油环氧值为7.34%,比相同反应时间内非超声反应得到的大豆油环氧值提高了29.23%,而且在达到相同环氧值时,超声条件比非超声条件的反应时间缩短了一半以上.试验结果表明:超声作用可以提高油脂的环氧值,缩短环氧化反应的时间.

In this research,soybean oil was epoxidized under ultrasonic conditions in the presence of formic acid as the reactive oxygen carrier and sulfuric acid as the catalyst.The parameters affecting the epoxy value of soybean oil,such as the amount of sulfuric acid,the molar ratio of formic acid to hydrogen peroxide,the ultrasonic frequency,the power,the temperature and the time,were discussed.The optimum conditions were as follows： catalyst 2.0%（W/W）,formic acid 20%（W/W）,the molar ratio of hydrogen peroxide to formic acid 7.76∶1,ultrasonic frequency 100 kHz,power 120 W,temperature 65 ℃,and ultrasonic time 45 min.Under the optimum conditions,the ESBO value was 7.34%,which was higher than the epoxy value obtained by the non-ultrasonic reaction in the same reaction time by 29.32%.The reaction time of the ultrasonic reaction was reduced by more than 50% in comparison with that of the non-ultrasonic reaction when achieving the same epoxy value.The results show that the ultrasonic reaction can increase the epoxy value of oils and shorten the epoxidation time.