基本信息:
- 专利标题： LOW TEMPERATURE PROCESSES FOR RECYCLING POLY(ETHYLENE TEREPHTHALATE)
- 申请号：PCT/US2022/047637 申请日：2022-10-25
- 公开(公告)号：WO2023076200A1 公开(公告)日：2023-05-04
- 发明人： BOAZ, Neil, Warren , STAPLETON, Jennifer, Lloyd
- 申请人： EASTMAN CHEMICAL COMPANY
- 申请人地址： 200 South Wilcox Drive
- 专利权人： EASTMAN CHEMICAL COMPANY
- 当前专利权人： EASTMAN CHEMICAL COMPANY
- 当前专利权人地址： 200 South Wilcox Drive
- 代理机构： TAYLOR POLK, Tammye, L.
- 优先权： US63/262,976 2021-10-25
- 主分类号： C07C67/03
- IPC分类号： C07C67/03 ; C07C69/82
摘要：
Processes are provided for the conversion of diglycol terephthalates to a dialkyl terephthalate, specifically bis(hydroxyalkyl) terephthalate to dimethyl terephthalate at low temperatures. The process involves initial catalyzed transesterification of bis(hydroxyalkyl) terephthalate with methanol at a first temperature of between 0°C and 70°C for an initial time followed by a second stage of the reaction at or below 30°C. In particular, the process is tolerant of significant amounts of glycol and water, so the precursor bis(hydroxyalkyl) terephthalate does not necessarily need to be highly pure or dry. Filtration of the reaction mixture allows recovery of high yields of dimethyl terephthalate of sufficiently high purity such that further purification is often not required in order to be repurposed for the manufacture of polyesters.