Preparation of Dimethyl Terephthalate by Depolymerization of Polyester
The aim of the study is to employ a novel homemade catalyst as a substitute for traditional catalysts,aiming to enhance the degradation rate of phthalic acid and the yield of dimethyl phthalate,thereby improving the recycling process of polyethylene terephthalate(PET).The controlled variable method is utilized,with a fixed amount of PET set at 2.5 g.Methanol is added at three times the amount of PET,while the homemade catalyst is added at 0.2%of the PET amount[n(homemade catalyst)∶n(PET bottle chips)∶n(methanol)is 1∶12∶39].The reaction is carried out in a hydrothermal reactor at a controlled temperature of 180℃for a duration of 60 min.The results demonstrate that under the specified conditions,the degradation rate of PET reaches 89.99%,and the yield of dimethyl phthalate attains 92%.In comparison with traditional catalysts,the novel homemade catalyst exhibits a considerable improvement in productivity.The adoption of the novel homemade catalyst significantly enhances both the degradation rate of PET and the yield of dimethyl phthalate,providing an effective approach for the recycling of PET.The application prospects of the novel catalysts in PET recycling process are broad.