用水滑石前驱体制备了Mg Fe O和Mg Fe Al O氧化物催化剂,研究了该催化剂在CO2气氛中乙烷脱氢催化活性。实验结果表明,添加Mg和Al元素有利于催化活性和乙烯收率的提高。MgFe0 5Al0 5Ox样品的活性较好,在700℃和V(CO2)/V(C2H6)=7时,乙烷...用水滑石前驱体制备了Mg Fe O和Mg Fe Al O氧化物催化剂,研究了该催化剂在CO2气氛中乙烷脱氢催化活性。实验结果表明,添加Mg和Al元素有利于催化活性和乙烯收率的提高。MgFe0 5Al0 5Ox样品的活性较好,在700℃和V(CO2)/V(C2H6)=7时,乙烷转化率20 6%,乙烯收率18 8%。CO2的作用是通过逆水煤气变换反应(CO2+H2 CO+H2O)推动乙烷脱氢反应并提高乙烯的选择性,通过CO2+C 2CO反应消除表面积炭提高催化剂的稳定性。展开更多
New Al4C3-containing Al-Ti-C master alloys (Al-0.6Ti-1C and Al-1Ti-1C) were developed by introducing Ti element into Al-C melt using melt reaction method,in which most of the TiC particles distribute around Al4C3 part...New Al4C3-containing Al-Ti-C master alloys (Al-0.6Ti-1C and Al-1Ti-1C) were developed by introducing Ti element into Al-C melt using melt reaction method,in which most of the TiC particles distribute around Al4C3 particles. It is believed that most of the C firstly reacts with Al melt and form Al4C3 particles by the reaction Al(l)+C(s)→Al4C3(s),and after adding Ti into the Al-C melt,the size of Al4C3 particles is decreased and the distribution of Al4C3 is improved through the reaction Ti(solute)+Al4C3(s)→ TiC(s)+Al(l). With the addition of 1% Al-1Ti-1C master alloy,the average grain size of AZ31 is reduced sharply from 850 μm to 200 μm,and the grain morphology of α-Mg transits from a fully-developed equiaxed dendritic structure to a petal-like shape. Al-C-O-Mn-Fe compounds are proposed to be potent nucleating substrates for primary Mg. Appropriate addition of Ti is believed to increase the grain refinement efficiency of Al4C3-containing Al-Ti-C master alloys in AZ31 alloy.展开更多
文摘用水滑石前驱体制备了Mg Fe O和Mg Fe Al O氧化物催化剂,研究了该催化剂在CO2气氛中乙烷脱氢催化活性。实验结果表明,添加Mg和Al元素有利于催化活性和乙烯收率的提高。MgFe0 5Al0 5Ox样品的活性较好,在700℃和V(CO2)/V(C2H6)=7时,乙烷转化率20 6%,乙烯收率18 8%。CO2的作用是通过逆水煤气变换反应(CO2+H2 CO+H2O)推动乙烷脱氢反应并提高乙烯的选择性,通过CO2+C 2CO反应消除表面积炭提高催化剂的稳定性。
基金Project(50625101) supported by the National Natural Science Foundation for Distinguished Young Scholars of ChinaProject(106103) supported by Key Project of Science and Technology Research of Ministry of Education of China
文摘New Al4C3-containing Al-Ti-C master alloys (Al-0.6Ti-1C and Al-1Ti-1C) were developed by introducing Ti element into Al-C melt using melt reaction method,in which most of the TiC particles distribute around Al4C3 particles. It is believed that most of the C firstly reacts with Al melt and form Al4C3 particles by the reaction Al(l)+C(s)→Al4C3(s),and after adding Ti into the Al-C melt,the size of Al4C3 particles is decreased and the distribution of Al4C3 is improved through the reaction Ti(solute)+Al4C3(s)→ TiC(s)+Al(l). With the addition of 1% Al-1Ti-1C master alloy,the average grain size of AZ31 is reduced sharply from 850 μm to 200 μm,and the grain morphology of α-Mg transits from a fully-developed equiaxed dendritic structure to a petal-like shape. Al-C-O-Mn-Fe compounds are proposed to be potent nucleating substrates for primary Mg. Appropriate addition of Ti is believed to increase the grain refinement efficiency of Al4C3-containing Al-Ti-C master alloys in AZ31 alloy.