Pd-Cu/TiO_2纳米纤维催化还原地下水硝酸盐的研究

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• 英文论文题名：Pd-Cu/TiO_2 Nanofiber Catalyst for Selective Reduction of Water Phase Nitrates
• 论文作者：王俏 ; 王威 ; 崔福义
• 英文论文作者：Qiao Wang ; Wei Wang ; Fuyi Cui ; State Key Laboratory of Urban Water Resources and Environments (SKLUWRE) ; School of Municipal and Environmental Engineering ; Harbin Institute of Technology
• 年：2016
• 作者机构：哈尔滨工业大学市政环境工程学院城市水资源与环境国家重点实验室;
• 论文关键词：静电纺丝 ; 原位制备 ; 双金属负载 ; 催化反硝化
• 会议召开时间：2016-07-01
• 会议录名称：中国化学会第30届学术年会摘要集-第三十七分会：纳米催化
• 语种：中文
• 分类号：TU991.26;O643.36
• 学会代码：ZGHY
• 会议名称：中国化学会第30届学术年会-第三十七分会 ; 纳米催化
• 会议地点：中国辽宁大连
• 主办单位：中国化学会
• 学会名称：中国化学会
• 页数：2
• 文件大小：241k
• 原文格式：D
• 会议级别：全国

摘要

硝酸盐(NO3-)是以地下水为饮用水水源的净水工艺中必须解决的问题之一,尤其是在小型水处理中,催化反硝化法被认为是最有发展前景的饮用水脱氮工艺,其中,催化剂的性能是制约该工艺发展的关键因素。据此,本研究提出了以Pd-Cu/TiO_2纳米纤维为催化剂构建催化反硝化体系去除水中NO_3~-的技术工艺。本研究采用静电纺丝法制备了钯铜双金属原位负载的二氧化钛纤维催化剂Pd-Cu/TiO2,活性金属平均粒径为6.8nm,钯铜分散均匀,无明显团聚。制备了不同钯铜负载比的催化剂,根据催化反硝化实验确定钯铜比为1:1时,催化剂性能最优。将该催化剂应用到催化反硝化体系中,研究了不同实验条件对NO_3~-去除效能的影响,并结合工程实际对其进行了优化,结果表明,pH为3.2、H_2流量为90mL/min为最优条件;并探讨了NO_3~-的催化加氢机制及催化剂稳定性。在优化条件下处理30mg/L的NO_3~-,去除率可达92.9%,整体氮选择性为86.2%,最大氮选择性可达94%,优于绝大多数催化剂,证实了本文制备的Pd-Cu/TiO_2纤维催化剂可以有效提高催化脱硝性能。
A novel titanium dioxide supported Pd-Cu bimetallic nanofiber(Pd-Cu/TiO_2) is developed by electrostatic spinning and then applied in the catalytic reduction of water phase nitrate(NO_3~-) to nitrogen gas(N_2).The as-prepared bimetallic nanofiber were well-dispersed,and the average size of active metal in TiO_2 nanofibers was6.8 nm.Five kinds of Pd-Cu/TiO_2 nanofiber with different Pd-Cu mass ratios are prepared,and based on the experimental results,the 1:1 Pd-Cu mass ratio is selected to be the optimum ratio.Pd-Cu/TiO_2 nanofibers exhibit a high NO_3~--N removal(92.9%) and N_2 selectivity(86.2%) in the denitrification.In addition,the catalytic activity is calculated to be 0.284 mg NO_3~--N/(g_(cata)·min).Compared with other Pd-Cu catalysts prepared by the conventional impregnation method,this Pd-Cu/TiO_2 nanofiber can provide more sites for nitrate reduction,and accurate control of active composition loading,which can dramatically promote performance in the catalytic denitrification.

引文

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