熔融结晶法提纯邻碘苯胺工艺

Purification of o-iodoaniline by melt crystallization

利用熔融结晶法对邻碘苯胺混合物进行分离提纯,考察并分析了降温速率、结晶终温、养晶时间、升温速率和发汗终温对产品收率和纯度的影响。邻碘苯胺质量分数为70. 95%时的最佳结晶工艺:以降温速率0. 3 K/5 min降温到结晶终温301. 15 K,使固体熔融液结晶,养晶时间为2 h;再升温发汗,升温速率为0. 2 K/5 min,升到发汗终温至313. 15 K结束。实验得到质量分数为99. 07%的邻碘苯胺,产品收率为61. 75%。

Crude o-iodoaniline mixtures are separated and purified by melt crystallization. Effects of cooling rate,final temperature in the crystallization process,crystal growing time,heating rate and final temperature in the sweating process on the yield and purity of the product are investigated and analyzed.The results show that 99. 07% o-iodoaniline can be obtained with a yield of 61. 75% when the initial concentration of o-iodoaniline in crude mixtures is 70. 95%,the cooling rate is 0. 3 K·min-1,the final crystallization temperature is 301. 15 K,crystal growing time is 2 h and the heating rate in sweating process is 0. 2 K·min-1 and the final sweating temperature is 313. 15 K.