Adsorption and catalytic oxidation of elemental mercury over regenerable magnetic Fe-Ce mixed oxides modified by non-thermal plasma treatment

被引：82

作者：

Xu, Yang ^{[1
]}

Luo, Guangqian ^{[1
]}

Pang, Qicong ^{[1
]}

He, Shuangwu ^{[1
]}

Deng, Fangfang ^{[1
]}

Xu, Yongqing ^{[1
]}

Yao, Hong ^{[1
]}

机构：

[1] Huazhong Univ Sci & Technol, Sch Energy & Power Engn, State Key Lab Coal Combust, Wuhan 430074, Hubei, Peoples R China

来源：

CHEMICAL ENGINEERING JOURNAL | 2019年 / 358卷

基金：

中国国家自然科学基金;

关键词：

Mercury; Flue gas; Catalyst; Non-thermal plasma; Regeneration; Magnetism; FIRED POWER-PLANTS; PROGRAMMED DESORPTION METHOD; MODIFIED ACTIVATED CARBON; COMBUSTION FLUE-GAS; MODIFIED BIO-CHARS; COAL COMBUSTION; SIMULTANEOUS REMOVAL; PHASE MERCURY; FLY-ASH; TEMPERATURE;

D O I：

10.1016/j.cej.2018.10.145

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

This study proposes the novel application of non-thermal plasma treatment to improve the oxidation capacity of regenerable magnetic Fe-Ce mixed oxides (FCs) for the efficient removal of elemental mercury (Hg-0) from coal combustion flue gas. Sample characterization shows that the textural property, crystalline phases, and magnetic property of FCs undergo no obvious changes after plasma treatment. But greater Ce4+ concentration and richer lattice oxygen are generated on the treated FCs. The treated FCs exhibit far better Hg-0 removal performance compared to raw FC. The effects of treatment time (0-20 min), reaction temperature (100-250 degrees C), and flue gas components (SO2, NO, O-2, HCl and H2O) on Hg-0 removal performance are also discussed. Both Hg-0 adsorption capacity and adsorption rate evaluated at 150 degrees C for the treated FCs are extremely close to those obtained with a commercial activated carbon manufactured specifically for mercury removal from flue gas. Furthermore, the Hg-0 removal mechanism is proposed for the treated FCs. The treated FCs include separate active sites for Hg-0 adsorption and catalytic oxidation. Ce4+ species with greater oxidation state and lattice oxygen are largely consumed during the Hg-0 removal process. However, these components are replenished by subsequent non-thermal plasma treatment. Finally, the spent FCs can be effectively recycled through magnetic separation, thermal desorption, and non-thermal plasma treatment.

引用

页码：1454 / 1463

页数：10