食品抗氧化剂没食子酸正辛酯的绿色合成新工艺

Green synthesis of new process for food antioxidant n-octyl gallate

以硫酸氢钠为催化剂微波辅助催化合成没食子酸正辛酯。通过熔点测定、红外光谱分析对产品进行结构表征;研究了微波功率、反应时间、酸醇物质的量比、催化剂用量以及催化剂重复使用对酯收率的影响。通过正交实验确定了最佳的反应工艺条件:没食子酸0.025mol,微波功率360W,酸醇的物质的量比为1∶18,催化剂1.25g,反应时间15min,不加带水剂,该条件下,没食子酸正辛酯的收率可达91.2%。结果表明,硫酸氢钠作为催化剂用于合成没食子酸正辛酯具有较好的催化活性和重复使用性;与传统的加热方式相比,微波加热大大缩短反应时间,降低能耗。

n-octyl gallate was synthesized by n-octanol and gallic acid with sodium bisulfate as catalyst under microwave irradiation.The reaction products were structurally identified by means of melting point measurement and infrared （IR）spectral analysis.Factors affecting the yield of esterification, such as microwave irradiation power and time,molar ratio of gallic acid to n-octanol, dosage of catalyst and catalyst reuse were studied.Through orthogonal experiments,the optimum reaction conditions were as follows.0.025mol gallic acid, microwave power 360W,the molar ratio of gallic acid and n-octanol 1：18, dosage of catalyst 1.25 g, for 15min,with no water-carrying reagent.Under the above conditions,the yield of n-octyl gallate could reach up to 91.2%.The results indicated that sodium bisulfate had good catalytic activity and could be used repeatedly, over the traditional heating methods, the optimized method showed the advantages of shorter reacting time and lower energy consumption.