With the aim to effectively depolymerize polyethylene terephthalate(PET)under mild reaction conditions,PET methanolysis and dimethyl terephthalate(DMT)hydrolysis are integrated in a catalyst system.Firstly,methanolysi...With the aim to effectively depolymerize polyethylene terephthalate(PET)under mild reaction conditions,PET methanolysis and dimethyl terephthalate(DMT)hydrolysis are integrated in a catalyst system.Firstly,methanolysis of PET to DMT is achieved over Cu-Mg-Al oxide catalyst.Next,terephthalic acid(TPA)is prepared by DMT hydrolysis.It is found that hydrolysis of DMT to TPA can be promoted by introducing trace amount of water in this catalyst system.CuO-MgO-4.5Al_2O_(3)catalyst demonstrates the excellent catalytic performance for the depolymerization of PET with high conversion rate and TPA yield(100%and 99.5%,respectively)after reaction at 160℃for 6 h,which provides a new idea for the depolymerization of PET.展开更多
采用CALPHAD(CALculation of PHAse Diagrams)方法重新对Mg-Al-Gd三元系进行评估,获得一套自洽的热力学参数。用Mg_(x)(TM,Mg)_(6)(RE,Mg)_(8)热力学模型(TM=过渡金属,RE=稀土金属)描述长周期堆积有序相14H和18R。计算代表性的等温截面...采用CALPHAD(CALculation of PHAse Diagrams)方法重新对Mg-Al-Gd三元系进行评估,获得一套自洽的热力学参数。用Mg_(x)(TM,Mg)_(6)(RE,Mg)_(8)热力学模型(TM=过渡金属,RE=稀土金属)描述长周期堆积有序相14H和18R。计算代表性的等温截面、垂直截面、液相线投影图和相关的零变量反应,与实验数据进行比较,表明所得热力学参数的可靠性。绘制了整个三元体系的反应图,并对几种Mg-Al-Gd合金的Scheil凝固路径和相分数进行计算和分析,清楚地描述了凝固过程中各相的形成以及γ和LPSO相的相分数随Gd成分的变化,这些是影响Mg-Al-Gd合金的显微硬度、极限抗拉强度和屈服强度的重要因素。展开更多
文摘With the aim to effectively depolymerize polyethylene terephthalate(PET)under mild reaction conditions,PET methanolysis and dimethyl terephthalate(DMT)hydrolysis are integrated in a catalyst system.Firstly,methanolysis of PET to DMT is achieved over Cu-Mg-Al oxide catalyst.Next,terephthalic acid(TPA)is prepared by DMT hydrolysis.It is found that hydrolysis of DMT to TPA can be promoted by introducing trace amount of water in this catalyst system.CuO-MgO-4.5Al_2O_(3)catalyst demonstrates the excellent catalytic performance for the depolymerization of PET with high conversion rate and TPA yield(100%and 99.5%,respectively)after reaction at 160℃for 6 h,which provides a new idea for the depolymerization of PET.
基金The financial supports from the National Key Laboratory of Science and Technology on High-strength Structural Materialsthe National Natural Science Foundation of China(No.51771235)。
文摘采用CALPHAD(CALculation of PHAse Diagrams)方法重新对Mg-Al-Gd三元系进行评估,获得一套自洽的热力学参数。用Mg_(x)(TM,Mg)_(6)(RE,Mg)_(8)热力学模型(TM=过渡金属,RE=稀土金属)描述长周期堆积有序相14H和18R。计算代表性的等温截面、垂直截面、液相线投影图和相关的零变量反应,与实验数据进行比较,表明所得热力学参数的可靠性。绘制了整个三元体系的反应图,并对几种Mg-Al-Gd合金的Scheil凝固路径和相分数进行计算和分析,清楚地描述了凝固过程中各相的形成以及γ和LPSO相的相分数随Gd成分的变化,这些是影响Mg-Al-Gd合金的显微硬度、极限抗拉强度和屈服强度的重要因素。