CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Guanyu Liu,Huiyun Xia,Yanhui Niu,Xu Zhao,Gengtong Zhang,Lifang Song,Huaxin Chen
Practical significance in terms of the long-term effective application of photocatalytic coatings is greatly challenged by its easy pollution and poor self-cleaning performance. In this paper, a self-cleaning photocatalytic WO 3 -TiO 2 nanorod (MWT) /PDMS building coating (MWT coating) was prepared by spraying methods. The surface hierarchical structure fabricated by MWT and PDMS was a crux to construct a superhydrophobic surface, which endowed MWT coating with self-cleaning performance. Besides, the MWT coating exhibited prominent durability and antifouling property after 450 d practical application of the external wall. The excellent self-cleaning property of the coating was confirmed by the removal and resistance to the adhesion of powder particles. Meanwhile, the photocatalytic properties of MWT endowed MWT coating with the ability to degrade organic pollutants on the surface. The color difference of the coating polluted by methyl red was only 1.18 and 4.77 after 24 h UV and visible irradiation, respectively. This mutual benefit effect of self-cleaning and photocatalysis was also reflected in the degradation of NO. In the first five cycles, the degradation efficiency of NO decreased by 4.74% gradually under visible light due to the adhesion of oxidation products, and most of the MWT on the coating surface was regenerated after flushing, the PCD efficiency increased by 3.71%. Furthermore, after 30 days of outdoor weathering test, the PCD efficiency of MWT coating decreased by 11.74% and 12.05% under UV and visible light, respectively, which lays a foundation for the long-term effectiveness of the MWT coating in the process of use.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
·
IF 4.326
Shujun Sun,Jun Zhang,Changdong Sheng,Hui Zhong
A novel Na2SiO3/Fenton system was employed for NO removal from coal-fired flue gas in a bubble reactor. The NO removal efficiency of this system could reach 94.36% when the flue gas residence time was 3 s. The hydrolysis reaction of Na2SiO3 produced OH-, which made the solution alkaline, and the formation of iron-based colloids in the alkaline environment effectively catalyzed the generation of free radicals from H2O2, O2•– radicals, which was the main reason for the increase of NO removal efficiency. The reaction of H2O2 catalyzed by iron-based colloids increased the solution pH, which could not only further improve the NO removal efficiency but also enhance the useless decomposition of H2O2. Na2SiO3 could buffer the solution pH, which weakened the ineffective decomposition of H2O2 and prolonged the effective denitrification time. The X-ray diffraction and ion chromatography analysis showed that NO was finally converted to NO3– and NO2–.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Shengjun Yi,Pincai Lai,Guilin Ma,Jinjian Pan,Zhen Chen,Yuanhang Qin,Xingmao Jiang
Nanocatalysis plays an important role in chemical industrial production, environmental protection and etc. However, traditional catalyst preparation methods are generally labor-intensive, time-consuming and need high-temperature calcination, which are not conducive to the preparation of nanostructured catalyst. Therefore, developing a green and facile method for nano-sized catalyst preparation is very significative. In this work, a series of nano-sized Co 3 O 4 /CeO 2 catalysts with high specific surface area, high oxygen storage and homogeneous distribution of active species were synthesized via a glucose-urea (G-U method), and applied in NO oxidation The NO oxidation performance indicates that the 12.5% CoCe G−U catalyst prepared by the G-U method shows higher activity than those of catalysts prepared by the traditional methods (precipitation, hydrothermal and impregnation methods). The characterization results revealed that the CoCe G−U catalysts have the highest specific surface area, pore volume, content of surface Ce 3+ and Co 3+ among the catalysts. Moreover, the nano Co 3 O 4 is better dispersed on CeO 2 , which resulted in more active oxygen species on the surface of the catalysts prepared by the G-U method. Herein, the higher specific surface area, the smaller Co 3 O 4 nanoparticles, the more active oxygen species and the higher Ce 3+ and Co 3+ contents of the CoCe G−U catalyst lead to the more excellent NO oxidation performance. This work provides a green and efficient approach for the industrial production of nano-sized oxide catalysts.
研究领域:
环境科学
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材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Engineering
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2023
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IF 12.8
Xiaoyu Li,Xiaoshu Lv,Jian Pan,Peng Chen,Huihui Peng,Yan Jiang,Haifeng Gong,Guangming Jiang,Li'an Hou
Photocatalysis offers a sustainable avenue for the oxidative removal of low concentrations of NO x from the atmosphere. Layered double hydroxides (LDHs) are promising candidate photocatalysts owing to their unique layered and tunable chemical structures, and the abundant hydroxide (OH − ) moieties on their surfaces that are hydroxyl radical ( • OH) precursors. However, inferior charge separation and limited active sites on an LDH hinder its practical applications. Herein, we developed a facile N 2 H 4 -driven etching (et) approach that introduces dual Ni 2+ and OH − vacancies (Ni v and OH v ) into NiFe-LDH nanosheets (referred to as NiFe-LDH-et) that facilitate improved charge-carrier separation and the formation of active Lewis acidic sites (Fe 3+ and Ni 2+ exposed at OH v ). In contrast to inert pristine LDH, NiFe-LDH-et actively removes NO when illuminated with visible light. Specifically, Ni 76 Fe 24 -LDH - et etched in 1.50 mmol·L −1 N 2 H 4 solution removes 32.8% of the NO from continuously flowing air (NO-feed concentration: ∼500 parts per billion (ppb)) when illuminated with visible light, thereby outperforming most reported catalysts. Experimental and theoretical data reveal that the dual vacancies promote the production of reactive oxygen species ( • O 2 − and • OH) and the adsorption of NO on the LDH. In-situ spectroscopy revealed that NO is preferentially adsorbed at Lewis acidic sites, particularly exposed Fe 3+ sites, and then converted into NO + that is subsequently oxidized to NO 3 − without the formation of any of the more toxic NO 2 intermediate, thereby alleviating risks associated with its production and emission.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
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IF 10.7
Honghong Yi,Ruzhu Jia,Xiaolong Tang,Dongjuan Kang,Qingjun Yu,Fengyu Gao,Shunzheng Zhao,Yunpeng Liu
Electrocatalyst reduction of nitrogen oxides (NOx) in the industrial flue gas to synthesize NH3 can not only greatly improve the electrochemical efficiency of NH3 production, but also realize the emission reduction and resource utilization of air pollutants. Purposeful structural optimization of catalysts is a key research challenge in this field. Firstly, density functional theory (DFT) calculations found that the formation of surface oxygen vacancies could be promoted by constructing metal cation vacancies on the catalyst surface, which in turn optimized the NO adsorption configuration and improved the catalytic activity. By this guidance, CoAl layered double hydroxides (CoAl-LDH) nanosheets containing Al atomic vacancies were prepared by alkali etching. Experimental results show that a suitable alkali etching time with aqueous NaOH can significantly enhance the electrocatalytic activity of the CoAl-LDH nanosheets for NO reduction to NH3. Compared with pristine CoAl-LDH (0.097 mg cm-2 h-1), the NH3 yield rate reached 0.310 mg cm-2 h-1 at -1.1 V vs. the reversible hydrogen electrode after alkali etching for 4 h, which increased by 2.2 times. The catalyst characterization and theoretical calculation results indicate that the abundant frustrated Lewis pairs (FLPs) on the surface of catalysts containing cation vacancies are the origin of the enhanced activity.
研究领域:
材料科学
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环境科学
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电化学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
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2016
·Vol. 6
·期 14
·5543-5553
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IF 5.287
Xin Zhao,Lei Huang,Supawadee Namuangruk,Hang Hu,Xiaonan Hu,Liyi Shi,Dengsong Zhang
A novel Zr–CeVO4/TiO2 catalyst was developed for the selective catalytic reduction (SCR) of NO with NH3. Both TiO2 nanosheets (TiO2-NS) and nanoparticles (TiO2-NP) with different crystal facets were used as supports for the catalyst. It was found that the TiO2-NS-supported catalyst showed much better activity, stability and H2O/SO2 durability than the TiO2-NP-supported catalyst. In particular, the catalyst loading amount was much lower than those of previously reported vanadate-based SCR catalysts. The crystal structures and morphologies were analysed by X-ray diffraction (XRD), Raman spectroscopy and (high-resolution) transmission electron microscopy ((HR)TEM). The redox properties, surface active species and acid sites of the catalysts were investigated through hydrogen temperature-programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), ammonia and nitrogen oxide temperature-programmed desorption (NH3-TPD and NOx-TPD) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTs) experiments. The improved activity at lower temperature was due to the presence of more active oxygen species and Brønsted acid sites, as well as the formation of NO2 on the surface of the TiO2 nanosheets which have exposed (001) facets. The enhanced stability and H2O/SO2 durability of Zr–CeVO4/TiO2-NS was due to the limited formation of NH4NO3 and (NH4)2SO4/NH4HSO4. The excellent low operation temperature, low vanadium content and absence of WO3(MoO3) in this catalyst indicated that it has promising potential as a SCR catalyst for practical applications.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2022
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IF 8.047
Shaomian Liu,Yongjun Ji,Wenqing Xu,Jianling Zhang,Ruihuan Jiang,Liang Li,Lihua Jia,Ziyi Zhong,Guangwen Xu,Tingyu Zhu,Fabing Su
Developing efficient catalysts for low reaction-temperature catalytic reduction of NO by CO (CO–DeNO x ) is desirable but very challenging. Here, we report that hierarchically interconnected porous (HIP) Mn x Co 3- x O 4 spinels, synthesized by a facile citric acid-assisted sol–gel method, can act as highly efficient catalysts for CO–DeNO x . The obtained Mn 0.3 Co 2.7 O 4 displayed a much-enhanced catalytic performance with 87% NO removal at 100 °C and a wide active-temperature window (100–400 °C). Its superior activity stems from the following reasons: (i) the high-valence of Mn 3+ , Mn 4+ , and Co 3+ species in the Co–O–Mn structure enables the high catalytic activity and the effective redox-cycling of the Co 3+ and Co 2+ adsorption sites; (ii) the HIP structure can significantly enhance gas diffusion. This work offers an avenue to design metal oxide catalysts for CO–DeNO x by effectively controlling the doping metal concentration and oxidation states of the active components.
研究领域:
材料科学
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环境催化
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化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING & TECHNOLOGY
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2023
·Vol. 46
·期 10
·2217-2225
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IF 2.1
Shuangshuang Lv,Xianlong Zhang,Haoyang Dong,Shi Jin,Xinyu Wang
Manganese-antimony composite oxide catalysts were prepared for use in low-temperature selective catalytic reduction of flue gas, by adopting the strategy of passivation to regulate the valence state of the active component and control catalytic activity. Activity evaluation results found that MnSb 0.36 O y delivered 80 % NO conversion in the presence of SO 2 at 200 °C, and nearly 90 % conversion at 250 °C. Doping with Sb changed the surface micromorphology, resulting in a perforated porousness layered foam with a porous structure of tens of nanometers, which was conducive to molecular mass transfer of the reaction gas. Doping with Sb regulated the valence state of the active MnO x component, which diminished catalytic oxidation of SO 2 , thus promoting catalyst stability and limiting the toxic effect of SO 2 .
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Zhitao Han,Tian Lan,Zhiwei Han,Shaolong Yang,Jingming Dong,Deping Sun,Zhijun Yan,Xinxiang Pan,Liguo Song
Experiments were conducted to simultaneously remove NO and SO2 from simulated exhaust gas by cyclic scrubbing and online supplementing pH-buffered NaClO2 solutions in a bench-scale reactor. The effects of key operating parameters on pollutant removal performance had been investigated. The results suggested that an extremely high oxidant utilization rate could be obtained when the oxidant supplementing molar rate approached the oxidant consumption molar rate. Though co-existing SO2 in flue gas would consume a certain amount of the oxidant during the absorption process, the intermediate products of SO32– ions generated from SO2 hydrolysis might be in favor of NO2 absorption to some extent. The introduction of ethanol in scrubbing solution could enhance NOx removal performance largely, which was possibly because of its inhibition effect on SO32– oxidation. The reaction mechanism and reaction products in scrubbing solutions were also discussed roughly through theoretical calculations and ion chromatography analysis.
研究领域:
环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Zixun Fang,Yao Zhou,Yang Yang,Yidong Hou,Can Yang,Jinshui Zhang
Artificial Z-scheme photocatalytic systems, inspired by natural photosynthesis, have been widely employed for pollutant removal. In this study, we fabricated a ternary Z-scheme Bi 2 O 3 /Bi/porous carbon nitride (PCN) heterojunction with an intimately coupled interface through a simple EG-assisted solvothermal approach to improving photocatalytic performance of NO oxidation. The in-situ generated metallic Bi acts as an electron mediator, effectively accelerating the separation and transfer of photoexcited carriers. The unique Z-scheme charge transfer mechanism provides the strong redox abilities and isolates the active sites for specific reactions, thus promoting photocatalytic NO oxidation activity. As a result, the optimized Bi 2 O 3 /Bi/PCN sample achieved a NO removal efficiency of 94.6%, outperforming single-component catalysts and most previously reported heterojunction-based photocatalysts. Additionally, in-situ Fourier transform infrared spectroscopy was employed to propose the NO removal mechanism, offering valuable insight into the conversion pathway. Such a heterogeneous Z-scheme photocatalytic system with a strong redox ability, high charge-separation efficiency, and long-term stability, demonstrates significantly enhanced photoactivity for pollutant removal and is expected to attract increasing interest for other photocatalytic applications.
研究领域:
环境科学
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材料科学
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光催化技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Linfeng Miao,Shaopeng Pang,Xuetao Wang,Mengjie Liu,Yu Huang,Jing Zhu,Zhongli Ji
Different drying methods were used to prepare catalytic membranes for the simultaneous removal of dust and NO to explore their effect on the distribution of active components, with the structural properties, filtration performance, catalytic performance, and working mechanism of the preferred prepared catalytic membrane systematically investigated. The results indicated that microwave drying, in contrast to traditional electric drying with blasting, effectively inhibited the migration of the precursor solution to achieve uniform loading of active components, thus endowing the catalytic membrane with excellent catalytic activity. Meanwhile, the pore structure of the fibrous ceramic substrate was not almost affected by the loaded catalyst and still exhibited high porosity. These characteristics contributed to the development of a catalytic membrane with good filtration and catalytic performance, as well as superior adaptable NO concentration and filtration velocity properties. Therefore, fibrous ceramic-based catalytic membranes prepared using microwave assistance offer considerable application prospects for integrated purification of high-temperature flue gases. Furthermore, the removal of dust and NO was determined to follow the Eley–Rideal reaction mechanism and surface filtration mechanism of the residual dust cake, respectively.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 27
·期 14
·16963-16971
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IF 3.056
Gong Pijian,Li Chunyu,Li Xinxue
Marine diesel engines produce a lot of exhaust gas (NO, SO 2 ). Based on the situation that wet scrubbing methods have been already applied to ship desulfurization and seawater is easily accessible around the ships, this paper proposed a novel AOP (advanced oxidation process) of NaClO 2 (sodium chlorite) with Cl − (abundant Cl − exist in seawater) to remove NO from the flue gases of marine engines. The buffer capacity of NaAC (sodium acetate), the effect of Cl − concentration, and Cl − promotion mechanism on NO removal were investigated. The result showed that the existence of NaAC in solution could inhibit the rapid decline of the solution pH. The addition of Cl − achieved a remarkable promotion to NO removal at lower NaClO 2 concentration, which was due to the fast generation of ClO 2 from the promotion decomposition of NaClO 2 by Cl − in acidic condition. Then, the thermodynamic and dynamic mechanism of the generation of ClO 2 was intensively analyzed. And the mechanism of NO removal was discussed finally.
研究领域:
环境科学
·
化学工程
✓ 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）