Page 161 - 《精细化工》2021年第12期

第 38 卷第 12 期 精 细 化 工 Vol.38, No.12
2021 年 12 月 FINE CHEMICALS Dec. 2021

催化与分离提纯技术
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高分散性纳米级 Fe /BAC-φH -θ(t)催化剂催化还原 NO
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王焕然，李先春 ，李 丽，王思怡
（辽宁科技大学 化学工程学院，辽宁 鞍山 114051）

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摘要：以椰壳活性炭（BAC）为载体，采用 H 2 还原法制备出高分散性纳米零价铁催化剂〔Fe /BAC-φH 2 -θ(t)〕
〔φ 为 H 2 体积分数（0、0.05%、2%、100%）；θ 为煅烧温度（600、700、800 ℃）；t 为煅烧时间（1、3、5 h）〕，
采用固定床反应器考察了催化剂制备过程中 H 2 体积分数、煅烧温度及时间对催化剂分散性、催化还原 NO 性能、
催化剂再生以及 CO 对催化剂还原 NO 的影响。采用 XRD、TEM、SEM、XPS、N 2 吸附-脱附对催化剂进行了
表征，并对 CO 还原 NO 反应机理进行了推测。结果表明，催化剂活性随着 H 2 体积分数以及煅烧时间的增加逐
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渐增强，但随着煅烧温度的升高先升高后降低。Fe /BAC-100%H 2 -700(3)催化剂中 Fe 粒径达到 9 nm 且均匀分散
在 BAC 表面。在 325 ℃时该催化剂可使 NO 转化率达 100%，表现出了良好的 NO 脱除效果。还原 NO 过程中，
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Fe 逐渐被氧化成 Fe 3 O 4 ，导致催化剂最终失活，失活后的催化剂经再生处理后可恢复活性，CO 的加入可以还
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原 Fe 3 O 4 再次生成 Fe ，提供活性位点，有效地延长催化剂的寿命，减缓催化剂失活的速率。
关键词：CO；NO；零价铁；还原；纳米粒子；催化技术
中图分类号：TQ426；X701 文献标识码：A 文章编号：1003-5214 (2021) 12-2523-08

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Highly dispersed nano Fe /BAC-φH 2-θ(t) catalysts for the reduction of NO

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WANG Huanran, LI Xianchun , LI Li, WANG Siyi
（School of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, Liaoning, China）

Abstract: Coconut shell activated carbon (BAC) was used as support to prepare highly dispersed nano
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zerovalent iron catalysts [Fe /BAC-φH 2 -θ(t)] by hydrogen reduction method. Here, φ is the volume fraction
of H 2 (0, 0.05%, 2%, 100%), θ is calcination temperature (600, 700, 800 ℃) and t is calcination time (1, 3,
5 h). The effects of H 2 volume fraction, calcination temperature and time on the dispersion，catalytic
reduction of NO，regeneration of the catalyst and catalytic reduction of NO in the presence of CO were

investigated in a fixed bed reactor. The catalysts were characterized by XRD, TEM, SEM, XPS and N 2
absorption-desorption. The mechanism of CO reduction of NO was speculated. The results showed that the
activity of the catalyst enhanced gradually with the increase of H 2 volume fraction and calcination time,
while that first increased and then decreased with the increase of calcination temperature. In
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Fe /BAC-100%H 2-700(3), Fe nanoparticles had a particle size of 9 nm and were evenly dispersed on the
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surface of BAC. Fe /BAC-100%H 2-700(3) exhibited a good NO removal effect at 325 ℃ with a NO
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conversion rate of 100%. In the process of NO reduction, Fe was gradually oxidized to Fe 3O 4, leading to
the deactivation of the catalyst. The deactivation of the catalyst could be recovered after regeneration
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treatment. The addition of CO could reduce Fe 3O 4 and generate Fe active sites again, effectively extending
the life of the catalyst and slowing down the rate of catalyst deactivation.
Key words: carbon monoxide; nitric oxide; zero-valent iron; reduction; nanoparticles; catalytic technology

中国煤炭资源储备丰富，煤炭燃烧后释放的氮 危害人类健康。目前，选择性催化还原法（SCR）
氧化物会产生如酸雨、雾霾、臭氧空洞等环境问题， 是较为常用的一种烟气脱硝方法，常使用 NH 3 作为

收稿日期：2021-06-18; 定用日期：2021-07-26; DOI: 10.13550/j.jxhg.20210624
基金项目：国家自然科学基金（U1910215）
作者简介：王焕然（1995—），男，博士生，E-mail：huanr4585@163.com。联系人：李先春（1972—），男，教授，E-mail：xianchunli@
ustl.edu.cn。