42 results about "Diethyl terephthalate" patented technology

The present invention relates to the field of organic synthesis, and in particular to a system and method for polyester recycling co-producing bis(2-hydroxyethyl) terephthalate and 1,4-cyclohexanedimethanol. The system, in the direction of feed, sequentially comprises a polyester alcoholysis system, a solid filtration system, a solvent recovery system, and a diethyl terephthalate purification system, as well as a bis(2-hydroxyethyl) terephthalate preparation system and a 1,4-cyclohexanedimethanol preparation system, each connected to the diethyl terephthalate purification system. The present invention, by optimizing the process route for polyester recycling co-producing bis(2-hydroxyethyl) terephthalate and 1,4-cyclohexanedimethanol, first degrades a polyester into an intermediate product diethyl terephthalate, and then prepares bis(2-hydroxyethyl) terephthalate and 1,4-cyclohexanedimethanol from the diethyl terephthalate. In this way, two degradation products can be obtained simultaneously, especially addressing the current issue of the high production cost of 1,4-cyclohexanedimethanol, reducing the cost of polyester recycling, and making it more suitable for industrial application.

The present invention relates to the field of organic synthesis, and in particular relates to a system and method for recovering a polyester to prepare bis(2-hydroxyethyl) terephthalate. The system sequentially comprises, along a feeding direction, a polyester pretreatment system, a polyester alcoholysis system, a solid matter filtering system, a solvent recovery system, a diethyl terephthalate refining system and a bis(2-hydroxyethyl) terephthalate preparation system. In the present invention, by optimizing the process route for recovering a polyester to prepare bis(2-hydroxyethyl) terephthalate, i.e., first degrading a polyester into an intermediate product diethyl terephthalate and then preparing bis(2-hydroxyethyl) terephthalate from the diethyl terephthalate, the costs for recovering the polyester to prepare bis(2-hydroxyethyl) terephthalate can be reduced, and the yield of bis(2-hydroxyethyl) terephthalate can be improved, thereby making the method more suitable for industrial application.