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以乙酸酐和水杨酸为原料,AlCl3改性732#阳离子交换树脂为催化剂,通过超声辅助合成乙酰水杨酸.利用红外光谱和热重分析对改性732#阳离子交换树脂催化剂进行表征,在最佳反应条件乙酸酐与水杨酸摩尔比为2.5、反应时间为20min、反应温度为75℃、催化剂质量为水杨酸质量的8％、超声功率为50 W、析晶时间为2h下,乙酰水杨酸产率可达84.4％,催化剂重复使用5次后仍有较高催化活性.该法较传统方法催化效果好,无腐酸排放,易分离且后处理工艺简单,催化剂重复利用率高.“,”Acetosalicylic acid is synthesized by using salicylic acid and acetic anhydride as raw materials,alchlor modified cation exchange resin as catalyst assisted by ultrasound irradiation.As is shown in the results of characterization by means of Fourier transform infrared spectrum and thermogravimetric,the skeleton structure of the resin has experienced little changes after it is modified by A1Cl3 with complexation reaction.The maximum yield of acetosalicylic acid can reach 84.4％ under the following optimal reaction conditions that the molar ratio of acetic anhydride to salicylic acid is 2.5∶1,reaction lasts for 20 minute,reaction temperature is set at 75℃,the mass amount of catalyst is 8％ that of salicylic acid,ultrasonic power is 50 W and crystallization time spends 2 h.The catalyst can be reused for five times and still remains high catalytic activity.This method exhibits better catalytic performance than traditional methods,which has no humic acid emissions.The product is easy to separate,the post-treatment process is simple,and the recycling rate of catalyst stays high.