Process including glycolysis and subsequent purification for recycling
polyester materials
    1.
    发明授权
    Process including glycolysis and subsequent purification for recycling polyester materials 失效
    方法包括糖酵解和随后的纯化用于回收聚酯材料

    公开(公告)号:US5635584A

    公开(公告)日:1997-06-03

    申请号:US570177

    申请日:1995-12-07

    IPC分类号: C08G63/78 C08J11/24 C08G63/00

    摘要: A new process is described for recycling polyesters. In accordance with the described process, postconsumer or scrap polyester is reacted with glycol to produce a monomer or low molecular weight oligomer by depolymerization of the polyester. The monomer or oligomer, as the case may be, is then purified using one or more of a number of steps including filtration, crystallization, and optionally adsorbent treatment or evaporation. The monomer or oligomer thus produced is particularly suitable as a raw material for acid or ester based polyester production of packaging grade polyester material. Because the process includes purification steps, specifications for the previously used polyester material need not be strict.

    摘要翻译: 描述了一种用于回收聚酯的新工艺。 按照所描述的方法,后聚合物或废聚酯与二醇反应以通过聚酯的解聚产生单体或低分子量低聚物。 然后根据具体情况可以使用一个或多个步骤纯化单体或低聚物,包括过滤,结晶和任选的吸附剂处理或蒸发。 这样制备的单体或低聚物特别适用于包装级聚酯材料的酸或酯基聚酯生产的原料。 因为该方法包括纯化步骤,因此以前使用的聚酯材料的规格不必严格。

    Process for the recovery of terephthalic acid and ethylene glycol from
poly(ethylene terephthalate)
    2.
    发明授权
    Process for the recovery of terephthalic acid and ethylene glycol from poly(ethylene terephthalate) 失效
    从聚对苯二甲酸乙二醇酯回收对苯二甲酸和乙二醇的方法

    公开(公告)号:US5413681A

    公开(公告)日:1995-05-09

    申请号:US151637

    申请日:1993-11-15

    IPC分类号: B01D3/00 B01D3/14 C07C51/09

    摘要: A process useful for the recovery of terephthalic acid and ethylene glycol from poly(ethylene terephthalate) or its copolymers. The process is economical, beneficial to the environment and provides polymer grade terephthalic acid and ethylene glycol from post-consumer resin. The process is a six-step process including: (1) contacting a resin containing poly(ethylene terephthalate) with water at elevated temperature and pressure, (2) cooling the resulting mixture to provide a solid portion containing terephthalic acid and a liquid portion containing ethylene glycol, (3) recovery of the ethylene glycol from the liquid portion by distillation, (4) recovery of the terephthalic acid by heating the solid portion in the presence of water vapor at elevated temperature to produce a vapor containing terephthalic acid and water, (5) cooling terephthalic acid water vapor mixture to a temperature below the dew point of terephthalic acid and (6) collecting the polymer grade terephthalic acid. The polymer grade terephthalic acid and ethylene glycol provided by this process can be used to make high quality terephthalate homopolymers or copolymers for applications including clear bottles and fibers.

    摘要翻译: 用于从聚对苯二甲酸乙二醇酯或其共聚物中回收对苯二甲酸和乙二醇的方法。 该方法是经济的,有利于环境,并提供来自消费后树脂的聚合物级对苯二甲酸和乙二醇。 该方法是六步法,其包括:(1)在升高的温度和压力下使包含聚对苯二甲酸乙二醇酯的树脂与水接触,(2)冷却所得混合物以提供含有对苯二甲酸的固体部分和含有 乙二醇,(3)通过蒸馏从液体部分回收乙二醇,(4)通过在水蒸汽存在下在高温下加热固体部分来回收对苯二甲酸,以产生含有对苯二甲酸和水的蒸汽, (5)将对苯二甲酸水蒸气混合物冷却至低于对苯二甲酸露点的温度,和(6)收集聚合物级对苯二甲酸。 通过该方法提供的聚合物级对苯二甲酸和乙二醇可用于制备用于包括透明瓶和纤维的应用的高质量对苯二甲酸酯均聚物或共聚物。