Hydrotalcite-supported Pd-Cu catalyst for nitrate adsorption and reduction from water

来源 :Chinese Science Bulletin | 被引量 : 0次 | 上传用户:wangqin613117
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Hydrotalcite-supported Pd-Cu catalyst for nitrate adsorption and catalytic reduction from water is prepared by co-impregnation method and characterized by surface area (BET), X-ray diffraction (XRD), scanning electron microscope (SEM), trans- mission electron microscope (TEM) and X-ray pho- toelectron spectrum (XPS). The performance of ad- sorption and hydrogenation of nitrate was evaluated and compared with Al2O3, TiO2, and HZSM-supported Pd-Cu catalysts. The experimental results demon- strated that hydrotalcite-supported Pd-Cu catalyst exhibited a high surface area (185.3 m2/g) and mesopore structure (average pore diameter of 52.2 ?). The active metal clusters were homogeneously dispersed on the support, and the size of the most was less than 10 nm. Excellent adsorption for nitrate resulted from that nitrate ions were forced to enter the interlayer space when the calcined hydrotalcite re- generated layer structure in nitrate solution. The ad- sorption isotherm could be well described by the Langmuir model. The comparison between the ad- sorption and catalytic hydrogenation for nitrate using hydrogen indicated that nitrate reduction on hydro- talcite-supported Pd-Cu catalysts was a consecutive and dynamic adsorption and catalytic hydrogenation process. Compared with the Al2O3, TiO2, and HZSM- supported catalysts, hydrotalcite-supported Pd-Cu catalyst possessed higher catalytic activity and se- lectivity. The analysis on the dissolving of metals in the solution demonstrated that there was hydrolyza-tion on the surface of the hydrotalcite-supported Pd-Cu catalyst. However, the concentrations of dis- solved metals in the solution were lower than the standard executed in China. The activity of the hy- drotalcite-supported Pd-Cu catalyst for nitrate reduc- tion kept steady after repeated use. Hydrotalcite-supported Pd-Cu catalyst for nitrate adsorption and catalytic reduction from water is prepared by co-impregnation method and characterized by surface area (BET), X-ray diffraction (XRD) The performance of ad- sorption and hydrogenation of nitrate was evaluated and compared with Al2O3, TiO2, and HZSM-supported Pd-Cu catalysts. The experimental results demon-strated The hydrotalcite-supported Pd-Cu catalyst showed a high surface area (185.3 m2 / g) and mesopore structure (average pore diameter of 52.2%). The active metal clusters were homogeneously dispersed on the support, and the size of the most was less than 10 nm. Excellent adsorption for nitrate resulted from that nitrate ions were forced to enter the interlayer space when the calcined hydrotalcite-regenerated layer structure in nitrate solution. by the Langmuir model. The comparison between the ad- sorption and catalytic hydrogenation for nitrate using hydrogen indicates that nitrate reduction on hydro- talcite-supported Pd-Cu catalysts was a consecutive and dynamic adsorption and catalytic hydrogenation process. , and HZSM-supported catalysts, hydrotalcite-supported Pd-Cu catalyst possessed higher catalytic activity and se- lectivity. The analysis on the dissolving of metals in the solution that there was hydrolyzate on the surface of the hydrotalcite-supported Pd- However, the concentration of dis- solved metals in the solution were lower than the standard executed in China. The activity of the hy- drotalcite-supported Pd-Cu catalyst for nitrate reduction was steady after repeated use.
其他文献
四川省现有旱坡地近5000万亩,其中坡度10度以上的占63%,水土流失严重,生产效益之低在全国都是少有的,这对四川省现代化农业的发展极为不利。在各级政府领导下,全省开展农田基
试验于1981—1982年在本所内进行。土壤为白夹泥,肥力较低,有机质含量仅1.35%,晚稻整田时设置4个处理:①对照(不施稻草、不施氮肥);②亩施风干稻草 The experiment was car
我院1990年~1998年9月共作纤维支气管镜(FiberopticBronchoscopy,FB简称纤支镜)检查6852例,经FB确诊肺部少见疾病12例,其中少见肺部恶性肿瘤3例,占同期肺部恶性肿瘤1795例的0.16%,现报告如下。1临床资料1.... In our hospital from 1990 to
这次省政府机构改革 ,有的部门撤消 ,有的降格 ,有的合并 ,但省机关事务管理局升格 ,这体现了省委、省政府对机关后勤工作的重视 ,同时也对管理局工作提出了更新更高的要求。
本文依据资料统计、野外考察,确定了四川亚热带划分的标准,同时阐述其内部分异特征,进而分析其农业气侯资源并提出合理利用的建议。 Based on the data statistics and fiel
地貌具有相对稳定的空间位置和形态特征,控制着光、热、水、土的重新分配与物质移动,直接或间接地影响着土地的利用和农业生产,同时还以它的成因要素对植物的适生、定居和发
全面理解和把握教材,深入挖掘教材,利用基本知识、方法和思想,从非静电力的提供和感应电动势的公式两个方面区分感生电动势和动生电动势,理解两种电动势的来由、区别和联系,
美国著名的世界粮食、资源、环境问题专家—世界观察研究所所长L·R·弗洛恩,根据该所“1984年世界各国调查报告”,提出了关于土壤保护的论文。文中介绍了世界各国土壤侵蚀
在隧道施工过程中,经常会遇到软弱地质围岩,若不采用有效的施工方法,隧道施工安全、质量和进度很难保证,也必将使施工单位蒙受不必要的经济损失。通过对宕迭二级公路改建工程
本文采用文献资料法、比较分析法、马克思主义分析法等研究方法,结合我国国情,力求对我国知识产权和奥林匹克知识产权发展现状进行全面、系统地分析探讨,从中发现我国奥林匹