冬青油的合成工艺研究

Synthesis technology of wintergreen oil from salicylic acid and methanol

本文研究浓硫酸催化水杨酸与甲醇酯化反应制备冬青油的生产工艺,并利用折光仪和紫外光谱仪测试对产品进行了表征。通过考察催化剂种类、物料配比、反应时间、催化剂用量和反应温度对产率的影响,确定了制备冬青油的最佳工艺条件。结果表明,以浓硫酸为催化剂时催化活性最佳;当取水杨酸为6.9 g时,水杨酸与甲醇配比为1:20,浓硫酸用量为4 m L,在78℃下反应12 h,冬青油的产率最高,可达到82.9%。

n this paper, wintergreen oil（methyl salicylate） was synthesized from salicylic acid and methanolwhich are catalyzed by concentrated sulfuric acid. The resulted wintergreen oil was characterized by refractometerand ultraviolet spectroradiometer. To obtain the optimum condition, the influences of catalyst type, material ratio,reaction time, amount of catalyst and reaction temperature on the yield of wintergreen oil were investigated.Experimental results show that the concentrated sulfuric acid was the best catalyst for preparing wintergreen oil. Theoptimum reaction condition was determined as follows： the amount of salicylic acid of 6.9 g, the ratio of salicylic acidto methanol of 1：20, the amount of concentrated sulfuric acid of 4 ml, temperature of 78 ℃, reaction time of 12 h.Under the optimum condition, the yield of wintergreen oil can reach 82.9%.