摘要
聚对苯二甲酸乙二酯(PET)是一种基于石油基衍生的具有良好性能的聚酯塑料,应用极为广泛,但其良好的稳定性导致其废弃后在自然界中难以降解,而回收PET目前最有效的方式是化学回收。笔者以钛酸酯和苯甲酸为原料,采用一锅法制备了苯甲酸钛催化剂,并用于催化乙二醇降解聚废旧PET的反应中,以醇解反应得到的对苯二甲酸双羟基乙酯(BHET)的收率为指标,探究了溶剂用量、催化剂用量和反应温度对收率的影响,并选用Box-Behnken设计响应面分析法探究了单因素间的交互作用对BHET收率的影响,对制得的催化剂及其解聚产物BHET进行相关的表征。结果表明:催化剂颗粒尺寸均匀,在解聚反应中有良好的催化性能,通过傅里叶变换红外光谱仪和差示扫描量热仪分析确定产物为BHET。在废旧PET用量为5 g、乙二醇溶剂质量为25 g、催化剂用量为PET质量的2.9%、反应温度为220℃、反应时间3 h的条件下,得到的BHET收率为87.2%。根据实验结果分析了醇解PET的反应机理,为高分子废弃物的降解及其他酯交换反应提供一定的参考。
Polyethylene glycol terephthalate(PET)is a polyester plastic with good properties based on petroleum-based derivatives and is used in a wide range of applications.Its good stability makes it difficult to degrade in nature after disposa,and chemical recycling of PET is currently the most effective way to recover it.In this paper,titanium benzoate catalysts were prepared by a one-pot method using titanate and benzoic acid as raw materials and used in the reaction to catalyze the degradation of poly-waste PET by ethylene glycol.The effect of solvent dosage,catalyst dosage,and reaction temperature on the yield of bis-hydroxyethyl terephthalate(BHET)obtained from the alcoholysis reaction was investigated,and the Box-Behnken design response surface analysis was chosen to investigate the effect of single-factor inter.The effect of interaction between single factors on the yield of BHET was investigated by Box-Behnken design response surface analysis.The prepared catalyst and its depolymerization product BHET were characterized.The results show that the catalyst particle size is uniform and has good catalytic performance in the depolymerization reaction.The product is determined to be BHET by Fourier Transform Infrared Spectrometer and Differential Scanning Calorimeter analysis.When the waste PET quality is 5 g,the amount of glycol solvent is 25 g,the amount of catalyst is 2.9%of PET mass,the reaction temperature is 220℃,and the reaction time is 3 h,the yield of BHET is 87.2%.The reaction mechanism of alcoholysis of PET was analyzed according to the experimental results,which can provide some reference for the degradation of polymer waste and other ester exchange reactions.
作者
温瑞阳
沈国良
孟令慧
韩垚杰
周超
于洋
霍悦
徐世洁
卫杰
Wen Ruiyang;Shen Guoliang;Meng Linghui;Han Yaojie;Zhou Chao;Yu Yang;Huo Yue;Xu Shijie;Wei Jie(School of Petrochemical Engineering,Shenyang University of Technology,Liaoyang 111003,China)
出处
《工程塑料应用》
CAS
CSCD
北大核心
2023年第8期72-77,共6页
Engineering Plastics Application
关键词
一锅法
对苯二甲酸双羟基乙酯
废旧聚对苯二甲酸乙二酯
响应面法
乙二醇
one pot method
bis-hydroxyethyl terephthalate
waste polyethylene glycol terephthalate
response surface method
glycol
