ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 28
·期 46
·65487-65498
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IF 4.223
Zhou
Jiacheng,Shen Qicheng,Yang Jie,Tariq Muhammad,Sun Wei,Cao Limei,Yang Ji
Co 3 O 4 is a promising Hg 0 removal catalyst for industrial application. Operating temperature and low sulfur resistance are two of the main problems that hinder its industrial application in Hg 0 removal. Herein, a metal-organic framework (Co-BDC) was introduced as a sacrificial template to obtain the catalyst nano-sized Co 3 O 4 @C by calcination. Part of the organic ligands is carbonized during the calcination. Carbon wrapped Co 3 O 4 and reduced metal agglomeration. The optimal Hg 0 removal temperature of the existing cobalt oxide catalysts was always around 150 °C, but H 2 -TPR showed that the oxygen atoms on the Co 3 O 4 @C were more active than those on Co 3 O 4 , causing the Hg 0 removal temperature window of Co 3 O 4 @C to shift to lower temperatures. The Hg 0 removal efficiency of Co 3 O 4 @C could reach almost 100% even at 25 °C. In the meanwhile, Co 3 O 4 @C also showed a strong SO 2 resistance at ambient temperature. Experimental results and characterization proved that SO 2 did not compete with Hg 0 on the surface of Co 3 O 4 at low temperatures. On the contrary, it participated in the oxidation of Hg 0 . This is a great improvement for Co 3 O 4 catalyst in Hg 0 removal. It reduces the restrictions on the application of Co 3 O 4 in Hg 0 removal. Co 3 O 4 @C shows considerable potential as an Hg 0 removal catalyst.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2022
·
IF 4.654
Xue-Lei Duan,Yuan-Ming Cao,Chong Gao,Sheng-Li Niu,Yi-Wen Shen,Qi Guo,Jiao-Jiao Xie,Kai-Qiang He,Chun-Gang Yuan
One novel/multifunctional selenium-doped SrFeO3-δ/HNTs composite was fabricated and used for immobilization of gaseous mercury. The composite showed excellent performances for Hg0 removal via adsorption coupled with photocatalytic oxidation in visible-light conditions. The adsorption capacity of 4271.15 μg·g–1, rate of 5.0 μg·g–1·min–1, and removal efficiency of ∼100% were obtained under N2+O2, which was further confirmed by reaction kinetics. SrFeO3-δ was selenized into iron diselenide and a Se–Fe bond with high affinity toward Hg0. In addition, the yielding of •O2– and the separation of photoexcited electrons and holes (h+) promoted the photocatalytic oxidation of mercury. The composite with intrinsic magnetism could be easily recycled for reuse by magnetic separation. Moreover, the composite possessed favorable tolerance to the complicated flue gas. An online lab-built thermal decomposition system demonstrated that the immobilized Hg was primarily HgSe, which exhibited very high stability and low toxicity. Density functional theory (DFT) calculations proved that the composite was half metal with magnetism, indicating that Hg on Se-SrFeO3-δ/HNTs formed the stable structure releasing 1.055 eV. The doping of selenium promoted the charge transfer between O (2p) and Hg (6s), which also favored Hg0 removal. Se-SrFeO3-δ/HNTs with recyclability possess great potentials for Hg0 efficient removal and immobilization/detoxification from flue gas.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Yongpeng Ma,Jianghui Du,Yifei Wu,Haobing Yan,Ruiqi Liu,Xiaojing Zhang,Hongzhong Zhang,Liming Zhou,Wenjun Huang
Among the diverse pollutants emitted from coal-fired and non-ferrous metal smelting flue gas, Hg 0 and CO have emerged as globally concerning environmental pollutants. However, the simultaneous abatement of multiple pollutants remains a critical challenge to be addressed. In this study, cobalt nanoclusters (Co NCs) were anchored on the terminal oxygen of Ti-O on Ti 3 C 2 MXene and formed asymmetric oxygen vacancies Co-Ov-Ti via a one-step hydrothermal method, yielding Co NCs/Ti 3 C 2 MXene with a morphology of hierarchical nanosheet-assembled spheres for Hg 0 and CO catalytic oxidation. Co NCs/Ti 3 C 2 MXene exhibited excellent 44 % and 52 % of Hg 0 and CO simultaneous removal efficiency at the optimal temperature of 250 °C, respectively. DFT calculations combined with energy barrier modeling were employed to investigate the reaction pathways and energy variations during the catalytic oxidation of Hg 0 and CO. Specifically, Hg 0 oxidation follows the Eley-Rideal mechanism, with a rate-determining energy barrier of 2.11 eV, while CO oxidation adheres to the Langmuir-Hinshelwood mechanism, featuring a rate-determining barrier of 0.17 eV. In the co-catalytic oxidation process, competitive adsorption between Hg 0 and CO was observed, primarily manifested as competition for Ov on the catalyst surface. This study provides a novel strategy for the synergistic control of multi-pollutants in industrial flue gas.
研究领域:
环境催化
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材料科学
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大气污染控制
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物理化学
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纳米材料
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Zhilei Guo,Guohua Jing,Sara A. Tolba,Chung-shin Yuan,Yu-Hua Li,Xiaowei Zhang,Zhiwei Huang,Huawang Zhao,Xiaomin Wu,Huazhen Shen,Wenjie Xia
Transition metal oxide (TMO)-decorated TiO 2 catalysts excel at low-temperature Hg 0 oxidation. However, TMOs are typically found in large nanoparticles (NPs), resulting in a lower atom utilization efficiency. The current paper presents the design of an Au single atom (SA)-doped Ti 4+ defected TiO 2 (Au SAC-Ti 1-x O 2 ) and investigations concerning the influence of an O-Au-O coordination environment on Hg 0 oxidation. Au SAC-Ti 1-x O 2 was designed using an O-Au-O coordination environment and the O-Au-O orbital interaction was elucidated using density functional theory (DFT). The enhanced oxidative capability of lattice oxygen atoms and the interaction between Hg 0 and oxygen atoms were investigated. The O-Au-O coordination environment containing Au SAC Ti 1-x O 2 was then synthesized and characterized using X-ray absorption fine structure (XAFS), X-ray photoelectron spectroscopy (XPS), etc. Finally, Hg 0 oxidation catalytic activity was determined. Due to the increasing population of Au-O antibonding orbital interactions in the valence band, the bond order of O-Au-O in Au SAC Ti 1-x O 2 decreased significantly, thereby enhancing the oxidation ability of its adjacent oxygen atoms. Au SA and ultra-small Au clusters coexisted on a Ti 1-x O 2 catalyst, and the Hg 0 -oxidation efficiency at 150–200 °C was 14 times and 1.5 times greater than those of TiO 2 and 0.1 % Au/TiO 2 , respectively. Furthermore, Au SAC Ti 1-x O 2 was more resistant to the inhibition of SO 2 and NO. It provides an efficient method for developing highly active SA catalysts for Hg 0 oxidation.
研究领域:
催化化学
·
环境科学
·
材料化学
·
理论与计算化学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Mengyuan Yin,Yuqi Wan,Shuai Li,Xiaoting Zhao,Wenwen Zhang,Yun Zhang,Hua Wang
Mesoporous melamine-silver (MA-Ag) nanocomposites doped with carbon nitride quantum dots (CN QDs ) were fabricated simply by the controlled supramolecular self-assembly. It was discovered that the resulting nanoflower-like CN QDs @MA-Ag nanocomposites could exhibit the peroxidase-like catalysis, which could be specifically enhanced by Hg 2+ by forming [email protected] alloys. A double catalysis-based colorimetric method was thereby developed for the fast detecting of Hg 2+ and Hg 0 in wastewater samples, with the levels down to 0.050 nM and 18.3 nM, respectively. Moreover, strong visible-light-driven photocatalysis of the nanocomposites was demonstrated for oxidizing Hg 0 into Hg 2+ through photocatalytic H 2 O 2 production so as to realize the detoxification of Hg 0 in the environmental wastewater. Besides, the fabricated mesoporous CN QDs @MA-Ag nanocomposites with large specific surface areas might facilitate the high Hg adsorption through the powerful MA-Hg chelate interaction, showing the efficient adsorption and/or removal of total Hg. The catalysis-selective colorimetric analysis and photocatalysis-based detoxification removal of total mercury may promise for wide applications in the environmental monitoring and wastewater treatment of toxic heavy metals of mercury.
研究领域:
环境科学
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纳米技术
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分析化学
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材料科学
·
废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）