关键词: 废聚对苯二甲酸乙二醇酯塑料, 降解, 制备, 优化, 对苯二甲酸, 响应面法

Abstract: Terephthalic acid (TPA) was prepared from the degradation of waste polyethylene terephthalate (PET)with microwave-assisted and alkali catalysis. The Box-Behnken center-united experimental design principles were applied. Dosages of catalyst and alkali, pyrolysis temperature and time were chosen as causal factors on the basic of single-factors experiments. The responsive surface analysis of 4-factors-3-levels was adopted. The quadratic surface model of TAP yield was established. The optimum combination was obtained. The structure and property of TPA were determined. Results indicated that TPA yield and the four factors conform with the quadratic model, the linear and quadratic term of four factors, and the interaction between the dosages of catalyst and alkali have significant effects on the yield of TPA. Modified and verified experiments were completed after considering product performance and actual operation. The optimum parameters were determined, 2.7g TOMAB, 260mL 15%NaOH, 85℃, 2.2 h. Under these conditions, the average value of the actual yield of TPA in three replicated experiments is 97.53%, and it is not significantly different from the value of 98.59% predicted by the model. Results demonstrate that this method is feasible.

Key words: waste PET plastic, preparation, optimization, TPA, responsive surface methodology(RSM)