摘要
近年来,随着聚对苯二甲酸丁二醇酯(PBT)产能的急剧增加,副产品四氢呋喃(THF)市场供过于求的问题日益严重。为了提升THF的市场竞争力,提高装置THF产品质量,基于THF水溶液共沸点随压力变化的特性及THF与1,4-丁二醇(BDO)、二氢呋喃、异丙醇等轻、重组分沸点的显著差异,采用三塔差压精馏技术对PBT生产过程中的酯化馏出物进行了深度提纯。工艺优化采用调整脱低沸物塔塔顶至预脱水塔流量、脱低沸物塔回流比等,在保证装置能耗稳定前提下降低产品中水含量。对精馏体系进行全组分分析,确定异丙醇为关键痕量杂质,基于预脱水塔原始设计参数及塔内温度场特性,在预脱水塔增设侧线采出装置,实现异丙醇定向分离,杂质脱除率达98%。优化调整后,THF产品纯度达到99.985%,水含量为45μg/g。
In recent years,with the sharp increase in polybutylece terephthalate(PBT)production capacity,the problem of oversupply in the market for its by-product THF has become increasingly severe.In order to enhance the market competitiveness of THF,this study focused on improving the quality of THF produced by a certain plant.Based on the characteristic that the azeotropic point of THF aqueous solution varies with pressure and its significant difference in boiling points from light and heavy components such as BDO,dihydrofuran,and isopropanol,a three-tower differential pressure distillation technology was utilized to deeply purify the esterification distillate in the PBT production process.Process optimization adopted a multi-dimensional control strategy,including adjusting the light ends removal column top overhead flow to predrying column and optimizing the light ends removal column reflux ratio,which reduced the water content in the product while maintaining stable energy consumption.A full-component analysis of the distillation system identified isopropanol as the key trace impurity.Based on predrying column's original design parameters and temperature field characteristics,a side-stream withdrawal device was added at predrying column,achieving directional separation of isopropanol with a 98%impurity removal rate.After optimization,the THF product purity reached 99.985%with water content reduced to 45μg/g.
作者
高甲
李世元
史路飞
辛英芸
Gao Jia;Li Shiyuan;Shi Lufei;Xin Yingyun(PBT Department of Sinopec Yizheng Chemical Fibre Co.,Ltd.,Yizheng Jiangsu 211900,China)
出处
《合成技术及应用》
2025年第2期58-62,共5页
Synthetic Technology & Application
关键词
聚对苯二甲酸丁二醇酯
酯化馏出物
四氢呋喃
差压精馏
流股分析
纯度
polybutylece terephthalate
esterification distillate
tetrahydrofuran
differential pressure distillation
stream analysis
purity
