Method for recovery preparation of high purity PET chip

Abstract

The invention discloses a method for recycling and preparing high-purity PET slices. After the waste PET material is processed by a kneader, it is dissolved in a propylene glycol solution, filtered, cooled and crystallized, and then squeezed twice, dissolved and crystallized to obtain a BHET refined cake, which is then dissolved, crystallized and distilled with deionized water to obtain high The pure BHET powder is prepared by polycondensation reaction to obtain high-purity PET chips. The invention solves the bottleneck that the traditional technology can only recycle the cleaned and dried bottle flakes and the clean waste silk of the fiber factory, greatly reduces the complexity of equipment requirements, reduces the demand for solvents, reduces energy consumption, and improves Recycling the finished product rate and product purity, reducing the cost, no secondary pollution, realizing a high degree of recycling and reuse of waste plastics, and enabling industrial production.

Description

technical field [0001] The invention relates to waste PET recycling technology, in particular to a method for recycling and preparing high-purity PET slices. Background technique [0002] At present, the main methods of recycling waste PET materials in my country are chemical degradation and physical methods. The chemical method is to degrade the PET material under the action of heat and chemical reagents to form low-molecular products, which can be further utilized, such as monomers can be repolymerized, and oil products can be further processed, but this method requires high temperature and high pressure, which requires a lot of equipment. High conditions, high energy consumption, and harsh conditions make it difficult to achieve large-scale operations; the physical method is a recycling technology for reprocessing waste PET through cutting, crushing, heating and melting, but the performance of recycled PET is much higher than that of new materials. Reduced, and contains ...

AI Technical Summary

Problems solved by technology

The chemical method is to degrade the PET material under the action of heat and chemical reagents to form low-molecular products, which can be further utilized, such as monomers can be repolymerized, and oil products can be further processed, but this method requires high temperature and high pressure, which requires a lot of equipment. High conditions, high energy consumption, and harsh conditions make it difficult to achieve large-scale operations; the physical method is a recycling technology for reprocessing waste PET through cutting, crushing, heating and melting, but the performance of recycled PET is much higher than that of new materials. Reduced, and contains a lot of impurities, the application value is greatly reduced

Printed PET film can not be processed and recycled due to easy foaming, broken particles, blackened color and odor in the physical treatment, which is still a blank area in technology