In order to improve the activity and eliminate some impurities, pretreatment wasused before hydrothermal synthesis. The fly ash was mixed with an aqueous NaOH solution, the alkali melted fly ash was also adopted, whic...In order to improve the activity and eliminate some impurities, pretreatment wasused before hydrothermal synthesis. The fly ash was mixed with an aqueous NaOH solution, the alkali melted fly ash was also adopted, which is hydrothermally treated at about104^(。)C, and the liquid/solid ratio was controlled at 6:1. In order to control Si/AI molar ratio,SiO_2 or AI_2O_3 powers were added to the fly ash. The results of XRD and SEM show thatthe alkali melted can activate fly ash and eliminate its quartz and mullite, along with theimprovement of Si/AI molar ratio and alkalinity. In addition, zeolite Na-A changes into sodalite gradually, and nepheline is the synthesized intermediate product. Those resultswere discussed on the basis of a formation mechanism of zeolite from fly ash.展开更多
利用Fe Ni Al Co Ti多元扩散偶研究了界面处的α1+α2+(FeCo)2Ti三相在800℃下的相平衡,通过扩散偶界面两侧的相成分分析获知,Co在α2与α1相之间的分配比约为1 1,Ti在α2与α1相之间的分配比约为2 5.在Fe Ni Al合金中同时添加Co与Ti时...利用Fe Ni Al Co Ti多元扩散偶研究了界面处的α1+α2+(FeCo)2Ti三相在800℃下的相平衡,通过扩散偶界面两侧的相成分分析获知,Co在α2与α1相之间的分配比约为1 1,Ti在α2与α1相之间的分配比约为2 5.在Fe Ni Al合金中同时添加Co与Ti时,其在固溶体α2与α1相之间的分配特征与Fe Ni Al Co和Fe Ni Al Ti系中一样,Co与Ti在α2与α1相之间的分配比仍均大于1.展开更多
采用分步沉积法制备不同Sr/Ti摩尔比例的Sr/Ti O2催化剂,以X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外(FT-IR)光谱、紫外-可见漫反射光谱(UV-Vis RDS)等手段对样品进行了表征,以可见光催化降解亚甲基蓝为模型反应...采用分步沉积法制备不同Sr/Ti摩尔比例的Sr/Ti O2催化剂,以X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外(FT-IR)光谱、紫外-可见漫反射光谱(UV-Vis RDS)等手段对样品进行了表征,以可见光催化降解亚甲基蓝为模型反应考察样品光催化活性.结果表明,催化剂的活性和结构随Sr/Ti摩尔比(n(Sr)/n(Ti))的变化而变化,当n(Sr)/n(Ti)≤3/2时,催化剂呈由Ti O2和Sr Ti O3组成的球状结构;而当n(Sr)/n(Ti)在3/2与4/1之间时,催化剂呈片状结构,且随着n(Sr)/n(Ti)增大,催化剂组成由Sr Ti O3和Sr2Ti O4变为Sr2Ti O4和Sr(OH)2H2O;当n(Sr)/n(Ti)=9/1时,催化剂呈以Sr(OH)2H2O为主的针状结构.其中,n(Sr)/n(Ti)=4/1的样品表现出最高的光催化活性,一级反应速率为Sr Ti O3钙钛矿催化剂的5.0倍,商用P25的86.7倍.展开更多
基金Supported by the Henan Outstanding Youth Science Fund (0612002400)
文摘In order to improve the activity and eliminate some impurities, pretreatment wasused before hydrothermal synthesis. The fly ash was mixed with an aqueous NaOH solution, the alkali melted fly ash was also adopted, which is hydrothermally treated at about104^(。)C, and the liquid/solid ratio was controlled at 6:1. In order to control Si/AI molar ratio,SiO_2 or AI_2O_3 powers were added to the fly ash. The results of XRD and SEM show thatthe alkali melted can activate fly ash and eliminate its quartz and mullite, along with theimprovement of Si/AI molar ratio and alkalinity. In addition, zeolite Na-A changes into sodalite gradually, and nepheline is the synthesized intermediate product. Those resultswere discussed on the basis of a formation mechanism of zeolite from fly ash.
文摘利用Fe Ni Al Co Ti多元扩散偶研究了界面处的α1+α2+(FeCo)2Ti三相在800℃下的相平衡,通过扩散偶界面两侧的相成分分析获知,Co在α2与α1相之间的分配比约为1 1,Ti在α2与α1相之间的分配比约为2 5.在Fe Ni Al合金中同时添加Co与Ti时,其在固溶体α2与α1相之间的分配特征与Fe Ni Al Co和Fe Ni Al Ti系中一样,Co与Ti在α2与α1相之间的分配比仍均大于1.
文摘采用分步沉积法制备不同Sr/Ti摩尔比例的Sr/Ti O2催化剂,以X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外(FT-IR)光谱、紫外-可见漫反射光谱(UV-Vis RDS)等手段对样品进行了表征,以可见光催化降解亚甲基蓝为模型反应考察样品光催化活性.结果表明,催化剂的活性和结构随Sr/Ti摩尔比(n(Sr)/n(Ti))的变化而变化,当n(Sr)/n(Ti)≤3/2时,催化剂呈由Ti O2和Sr Ti O3组成的球状结构;而当n(Sr)/n(Ti)在3/2与4/1之间时,催化剂呈片状结构,且随着n(Sr)/n(Ti)增大,催化剂组成由Sr Ti O3和Sr2Ti O4变为Sr2Ti O4和Sr(OH)2H2O;当n(Sr)/n(Ti)=9/1时,催化剂呈以Sr(OH)2H2O为主的针状结构.其中,n(Sr)/n(Ti)=4/1的样品表现出最高的光催化活性,一级反应速率为Sr Ti O3钙钛矿催化剂的5.0倍,商用P25的86.7倍.
