PET酯化反应过程中的二甘醇生成

二甘醇(DEG)在聚对苯二甲酸乙二酯(PET)切片中的含量是PET的重要质量指标．在生产过程中必须严格控制。利用PET的工艺模拟模型，计算并分析了酯化反应器内DEG生成量及其影响因素，结果表明，第一酯化反应器出口的DEG质量分数为0．732％；第二酯化反应器出口的DEG质量分数为0．851％；影响DEG生成的反应因素按影响程度大小依次为：温度、配比、时间和压力。

Formation of DEG in PET esterification process

The content of diethylene glycol (DEG) in polyethylene terephthalate (PET) chip is a very important quality index and must be strictly controlled in PET production. This paper calculated and analyzed the DEG content inside the esterification reactor and the related effective factors by taking advantage of the simulation model of PET process. The results show that the mass fraction of DEG reaches 0.73% and 0.85% at exit of the first and the second esterification reactor, respectively. The reaction parameters that influence the formation of DEG can be ranked in the descendent sequence of temperature, proportioning, time and pressure in accordance with their effectiveness.