中文摘要：

采用熔融结晶法对甲醇合成油分离得到质量分数62．3％的均四甲苯富集液进行分离提纯以获得高纯度的均四甲苯副产品。实验中比较了静态结晶和鼓泡结晶的提纯效果，考察了鼓气速率、降温速率、结晶终温、结晶恒温时间、发汗终温和发汗恒温时间等操作参数对结晶过程的影响。最终确定了适宜的操作条件为速率比0．75L／（h·g）、降温速率0．1℃／min，结晶恒温时间1．5h和发汗恒温时间2h。对不同质量分数的富集液进行结晶和发汗实验，得到以结晶终温和发汗终温为变量的操作平衡曲线。对质量分数为62．3％的原料通过三级结晶分离提纯，就可以获得99％以上的均四甲苯产品。通过实验与计算结果表明，本文计算模型与实验数据吻合较好，可以满足工程需要。

英文摘要：

In order to get high-purity durene as by-product, melt crystallization was used to purify durene from mixtures containing mass fraction 62.3% durene which comes from the distillation cut of methanol synthetic oil. The experiment was carried out to compare the bubbling crystallization and study the effects of main parameters （bubbling speed, cooling rate, crystallization temperature, the holding time during crystallization, sweating temperature and the holding time during sweating） on the crystallization. The appropriate operating conditions were that rate ratio was 0.75 L/（ h · g） , cooling rate was 0.1 ℃/min, crystallization time was 1.5 h and sweating time was 2 h. By the experiments with durene solution of different mass fractions, the empirical crystallization and sweating equilibrium equations were developed. The mass fraction 62.3% durene solution was purified to more than 99% by three continuous crystallization stages. The calculated results fit well with the experimental data, which can satisfy the requirement of engineering.