Macrowave Depolymerization Of Polyethylene Terephthalate In Pure Water

The depolymerization of polyethylene terephthalate(PET) by microwave radiation in pure water is investigated.This process is that depolymerization of PET with microwave radiation needn't acid, base and catalyst .It is a new technology of recycling waste PET and of green chemistry. Some ways is investigated, for example: depolymerization products, chain scission mechanism, reaction conditions and PET depolymerization kinetics. The result approve that Under the condition of 220℃, 2.0 MPa, 120 min, water /PET10 and 800W, PET is depolymerized completely, conversion of PET is 100%. It is testified that the depolymerized products are terephthalic acid(TPA), ethylene glycol(EG) and trace diethylene glycol(DEG). At the condition of the microwave irradiation power 600W, water/PET 10, 210℃, reaction mechanism is the random chain scission mechanism. Reaction temperature has important effection on the degree of PET depolymerization. weight ratio of water to PET has Effect on the degree of PET depolymerization, water to PET 10 is optimal. Microwave power has little effect on the degree of PET depolymerization. Activation energy is 38.5KJ/mol, microwave radiation have impaction on PET depolymerization with lowing activation energy.The depolymerization of polyethylene terephthalate(PET) by microwave radiation in pure water is green chemistry and in according with green chemistry principles. It is the powerful one of the depolymerization of polyethylene terephthalate ways .