工艺创新使DMT重返聚酯链

Process innovations bringing DMT back into the polyester chain

德国H＆GHegmanns公司和瑞士SulzerChemtech公司联合开发了一种改进的对苯二甲酸二甲酯(DMT)和精对苯二甲酸(PTA)工艺。该工艺以Witten-Katzschmann工艺与Sulzer公司环境友好的熔融结晶技术相结合为基础,改进的工艺把强化的氧化反应与有效的副产物和能量回收、改进的粗酯和副产物蒸馏塔系列,以及获得最终DMT纯度的熔融结晶技术结合在一起。如果需要的话,可以使DMT水解生产高纯度PTA。这些改进提供了新的机遇,使DMT／PTA工艺优化,获得最高的纯度,产生最少的废料以及综合的装置经济性。

An improved dimethyl terephthalate (DMT)/purified terephthalic acid (PTA) process has been jointly developed by H&G Hegmanns, Gelsenkirchen/Germany and Sulzer Chemtech, Winterthur/Switzerland. The process is based on enhancements to the Witten-Katzschmann process together with Sulzer's environmentally friendly melt crystallization technology. The improved process combines an enhanced oxidation reaction with efficient by-product and energy recovery, a revised raw ester and by-product distillation train, and a melt crystallization technology for the final DMT purification. If desired, the pure DMT can be subsequently hy-drolyzed to produce toppurity PTA. Together, these improvements allow new opportunities to optimize the DMT/PTA process for maximum purity, minimum residue and overall plant economy.