通过NDC与EG酯交换反应合成中间体2,6-萘二甲酸乙二醇酯(BHEN),采用正交实验设计方法,研究了BHEN缩聚反应合成PEN的影响因素,筛选出醋酸锌为反应催化剂、位阻酚1010为抗氧剂;并确定了其反应温度为295℃;每摩尔BHEN用催化剂的量为4×...通过NDC与EG酯交换反应合成中间体2,6-萘二甲酸乙二醇酯(BHEN),采用正交实验设计方法,研究了BHEN缩聚反应合成PEN的影响因素,筛选出醋酸锌为反应催化剂、位阻酚1010为抗氧剂;并确定了其反应温度为295℃;每摩尔BHEN用催化剂的量为4×10-4mol,反应时间为180 m in;每摩尔BHEN用抗氧剂的量为1×10-5mol.展开更多
Plastic waste management has emerged as a critical environmental issue due to the exponential increase in plastic consumption worldwide.Polyethylene terephthalate(PET)is extensively used in the production of water bot...Plastic waste management has emerged as a critical environmental issue due to the exponential increase in plastic consumption worldwide.Polyethylene terephthalate(PET)is extensively used in the production of water bottles,which constitutes a significant fraction of the plastic waste.PET recycling is a challenging task due to the lack of efficient and cost-effective depolymerization methods.In this study,we developed a microwave(MW)catalytic depolymerization method for PET recycling using modified zinc oxide loaded with manganese oxide as a cocatalyst.The modified Mn_(3)O_(4)/ZnO catalyst presents high efficiency in depolymerizing PET into its monomers with only 0.4 wt% ratio of the catalyst to PET at 175℃ for 5 min,resulting in 100% conversion of PET and 88% selectivity toward bis-hydroxyethyl terephthalate monomers.It is believed that Mn_(3)O_(4)provides additional Lewis acid sites,promoting the dissociation of glycol from PET,and the MW irradiation plays a crucial role in rapidly heating the ethylene glycol and the catalyst,thereby accelerating the PET depolymerization process.In addition,the heterogeneous nature of the catalyst facilitates its easy separation from the reaction mixture for reuse,simplifying the catalyst recovery process and enabling costeffective and sustainable PET recycling.Thus,this study provides an innovative and sustainable solution for PET recycling,contributing toward the circular economy and mitigating the environmental impact of plastic waste.展开更多
文摘通过NDC与EG酯交换反应合成中间体2,6-萘二甲酸乙二醇酯(BHEN),采用正交实验设计方法,研究了BHEN缩聚反应合成PEN的影响因素,筛选出醋酸锌为反应催化剂、位阻酚1010为抗氧剂;并确定了其反应温度为295℃;每摩尔BHEN用催化剂的量为4×10-4mol,反应时间为180 m in;每摩尔BHEN用抗氧剂的量为1×10-5mol.
基金UK EPSRC project(EP/S018204/2)Royal Society Leverhulme Trust Senior Research Fellowship(SRF\R1\21000153).
文摘Plastic waste management has emerged as a critical environmental issue due to the exponential increase in plastic consumption worldwide.Polyethylene terephthalate(PET)is extensively used in the production of water bottles,which constitutes a significant fraction of the plastic waste.PET recycling is a challenging task due to the lack of efficient and cost-effective depolymerization methods.In this study,we developed a microwave(MW)catalytic depolymerization method for PET recycling using modified zinc oxide loaded with manganese oxide as a cocatalyst.The modified Mn_(3)O_(4)/ZnO catalyst presents high efficiency in depolymerizing PET into its monomers with only 0.4 wt% ratio of the catalyst to PET at 175℃ for 5 min,resulting in 100% conversion of PET and 88% selectivity toward bis-hydroxyethyl terephthalate monomers.It is believed that Mn_(3)O_(4)provides additional Lewis acid sites,promoting the dissociation of glycol from PET,and the MW irradiation plays a crucial role in rapidly heating the ethylene glycol and the catalyst,thereby accelerating the PET depolymerization process.In addition,the heterogeneous nature of the catalyst facilitates its easy separation from the reaction mixture for reuse,simplifying the catalyst recovery process and enabling costeffective and sustainable PET recycling.Thus,this study provides an innovative and sustainable solution for PET recycling,contributing toward the circular economy and mitigating the environmental impact of plastic waste.
