PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2018
·Vol. 20
·期 35
·22744-22752
·
IF 3.906
Yiqing Zeng,Yanan Wang,Shule Zhang,Qin Zhong
In this paper, black TiO2 without adding active components was developed for NH3-SCR-DeNOx. The catalytic activity tests showed that the NO removal efficiency of black TiO2 was always greater than 90% at 330–390 °C, which almost reached that of the commercial NH3-SCR-DeNOx catalyst. XRD, UV-vis, TG, EPR, XPS, H2-TPR, DFT and NH3-TPD analyses were carried out to study the structure–effectiveness relationship. We found that a large number of oxygen vacancies were formed over the black TiO2 surface. It was not only promoted the adsorption of NH3via direct (oxygen vacancies as Lewis acid sites for NH3 adsorption) and indirect (oxygen vacancies promote the formation of surface hydroxyl groups, which are Brønsted acid sites for NH3 adsorption) forms, but also improved the redox properties by promoting the reduction of Ti4+ to Ti3+. These changes lead to the superior catalytic activity of black TiO2 for NH3-SCR-DeNOx. Additionally, an in situ DRIFT study demonstrated that the NH3-SCR-DeNOx reaction over black TiO2 occurred via the Eley–Rideal (E–R) mechanism. Finally, the catalytic stability and resistance to H2O and SO2 of the black TiO2 catalyst were studied, and it showed good performances. This study offered new and important insights into the understanding of the role of oxygen vacancies in determining the physical and chemical properties of catalysts.
研究领域:
环境催化
·
材料科学
·
物理化学
·
大气污染控制
·
表面科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2026
·
IF 3.9
Jia-Xin Zhang,Peng-Song Li,Guangwei Ma,Zhen Chen,Li Yang,Yuan-Hang Qin,Tielin Wang,Cun-Wen Wang
Nitrogen oxides (NOx) are harmful air pollutants, and their selective catalytic reduction by CO (CO-SCR) offers the dual benefit of removing both NO and CO, thus realizing the concept of “waste-to-value”. However, most CO-SCR catalysts are effective only at ≥300 °C, limiting low-temperature applications. Herein, we explore Ni–Cu mixed oxides (NiCuOx) that leverage the synergistic roles of Cu+ species and the Ni3+/Ni2+ redox cycle and the surface synergistic oxygen vacancies (SSOVs) that facilitate NO dissociation. NiCuOx catalysts were synthesized using three conventional methods─sol–gel, coprecipitation, and hydrothermal─as well as a less conventional microwave-assisted deep eutectic solvent (DES) method, and their CO-SCR performance was systematically evaluated. Among them, the DES-derived catalyst (DES-NiCuOx) exhibits superior catalytic performance, achieving 100% NO conversion above 120 °C and 100% N2 selectivity above 150 °C, ranking among the highest reported to date for nonprecious metal catalysts. This outstanding activity is attributed to its larger specific surface area; enriched Cu+ species and OVs, particularly SSOVs; and improved redox properties. In situ DRIFTS analysis reveals that interfacial Ni3+–□–Cu+ (where □ represents an OV) structures in DES-NiCuOx promote NO dissociation and CO adsorption. Moreover, the concurrent involvement of Langmuir–Hinshelwood and Mars–van Krevelen mechanisms, facilitated by excellent oxygen mobility and redox properties, plays a vital role in enhancing low-temperature CO-SCR efficiency. This work highlights the advantages of the DES synthesis route for preparing highly dispersed mixed metal oxides and provides new insights into the rational design of efficient catalysts for low-temperature NOx abatement.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Zhicheng Xu,Yuran Li,Junxiang Guo,Jin Xiong,Yuting Lin,Tingyu Zhu
In this work and for the first time, an alkali metal potassium (K) as a promoter was loaded on an activated carbon (AC) to be used for selective catalytic reduction of NO from industrial flue gas. The denitrification activity of K-modified AC samples was investigated and compared with those of acid- and Cu-modified AC samples. The three modifications can enhance the denitrification activity of AC samples. To investigate the enhanced mechanisms of denitrification and SO 2 resistance, various AC samples were characterized by SEM, EDX, XRF, ICP, XRD, N 2 physisorption, H 2 -TPR, XPS, in situ DRIFTS and TPD. For the acid modification, the content of phenolic hydroxyl increases and then promotes the adsorption of NH 3 . For the loading of Cu, the appearance of Cu 2+ /Cu + sites with high catalytic activity promotes NH 3 and NO adsorption and changes the reaction pathway. For the loading of K, the adsorption capacity for NO increases nearly 12 times higher than that on Raw-AC, of which 85.0% is chemical adsorption. Moreover, three kinds of active nitrate species additionally forms, including nitro compounds, monodentate nitrate and nitrous oxide, which promote the denitrification reaction path. AC-Cu has poor sulfur resistance due to the sulfation of Cu, while AC-K show good sulfur resistance due to the enhanced adsorption of NO. The catalytic dissociation activity of N 2 O on AC-K makes the formation and decomposition of N 2 O into a dynamic equilibrium. As a result, AC-K has a high N 2 selectivity , while AC-Cu has poor N 2 selectivity.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Yifan Li,Yaqin Hou,Yongzhao Zhang,Yatao Yang,Zhanggen Huang
Surface interface regulation is an important research content in the field of heterogeneous catalysis. To improve the interface interaction between the active component and matrix, tremendous efforts have been dedicated to tailoring the morphology, size, and structure of composite catalysts. In this work, we report a confinement strategy to synthesize a series of core-shell catalysts loaded with metal oxides on titania nanotubes (TNTs), which were applied to the selective catalytic reduction of NO x with ammonia. Interestingly, the core-shell catalyst with confinement of TNTs exhibited the remarkable activity at low temperature region, N 2 selectivity and sulfur tolerance. Benefiting from the superior interfacial confinement characteristic of TNTs and Fe 2 O 3 , strong component interactions, the surface acid sites and strong oxidizability of MnO x were properly regulated, thus obtained the outstanding activity, N 2 selectivity and provide chemical protection to effectively prevent SO 2 poisoning. As far as the reaction mechanism, we found that the adsorption and reactivity of Lewis acid sites were the dominant factors affecting the activity in the NH 3 -SCR process by in situ DRIFT spectra. In general, our work provides an innovative strategy for constructing an TNTs-enwrapped nanocomposite with nano-confinement and core-shell structure to improve the low temperature SCR process.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2022
·
IF 5.477
Kaiwen Ni,Yuewang Peng,Geyu Dai,Huawang Zhao,Zhiwei Huang,Xiaomin Wu,Guohua Jing,Wei Feng,Ye Yuan
Background Ammonia bisulfate (ABS) deposition on the active sites of the catalyst surface is the main reason for SO 2 poisoning in low-temperature NH3-selective catalytic reduction (SCR). Accelerated ABS decomposition efficiently enhances the SO 2 resistance. Methods In this work, ceria was specifically chosen to decorate V 2 O 5 -WO 3 /TiO 2 catalyst (Ce-VW/Ti) to activate ABS decomposition in low-temperature NH 3 -SCR. Significant findings The optimal 7Ce-VW/Ti catalyst accelerated the decomposition of ABS and had superior SO 2 tolerance at 250°C. The additive CeO 2 improved the specific surface area and surface acidity, favoring the NH 3 -SCR catalytic activity. ABS was preferentially deposited on the additive CeO 2 on the surface of the 7Ce-VW/Ti catalyst and generated cerium sulfate, eventually protecting the active V 2 O 5 sites and TiO 2 support. Moreover, high quantity of V 5+ and charge transfer between active species V 2 O 5 and support TiO 2 could be maintained due to CeO 2 protection, subsequently maintaining the high NH 3 -SCR performance and enhancing the SO 2 tolerance.
研究领域:
催化
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2023
·
IF 4.1
Shasha Huang,Yulong Shan,Xiaoyan Shi,Zhongqi Liu,Qiang Wang,Hong He
In the present work, we report on two passive NOx adsorber (PNA) material candidates: the novel support CeSnOx with and without Pd loading. The NOx adsorption and storage capacities of fresh and hydrothermally aged CeSnOx and Pd/CeSnOx were investigated. The results show that CeSnOx exhibits a rather large NOx uptake and storage capacity (28.9 μmol/g), while the loading of Pd on CeSnOx can further increase the storage capacity to 37.6 μmol/g and affect the desorption temperature of NOx. It was found that the NOx desorption temperature of Pd/CeSnOx was compatible with the efficient operating window of selective catalytic reduction (SCR) catalysts. After a hydrothermal aging treatment at 800 °C for 12 h, the NOx adsorption and storage capacities of CeSnOx and Pd/CeSnOx increased, indicating excellent hydrothermal stability. The interaction of Pd with CeSnOx, the state of Pd species, and the structure of CeSnOx and Pd/CeSnOx are studied by combination of the characterization results.
研究领域:
化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2026
·
IF 6.6
Jiahao Wei,Gonggang Sun,Zheng Hong,Qi Wang,Xinbao Li
Catalysts for NH 3 selective catalytic reduction (NH 3 -SCR) suffer from severe alkali metal poisoning, particularly by potassium (K). In this study, a series of K-resistant zirconium phosphate supported CeO 2 -SnO 2 catalysts (CeSn/ZrPs) were prepared by a hydrothermal-impregnation method and the simulated poisoning process with K loading amounts ranging from 1 wt% to 10 wt% was achieved by impregnating the catalysts with a KCl solution. The catalyst that contained 20 wt% Ce and 1 wt% Sn exhibited excellent SCR activity and K-poisoning resistance. The NO conversion over the CeSn/ZrP catalyst achieved 91.6% at 350 °C after 5 wt% K poisoning, and even retained 80.2% when the K content was increased to 8 wt%. The resistance mechanism of CeSn/ZrP against K-poisoning was studied by a series of characterizations. The results demonstrate that CeSn/ZrP exhibits a high surface area, strong acidity and enhanced redox properties due to Sn doping. The abundant Brønsted acid sites provided by the zirconium phosphate support played a crucial role in resisting K poisoning. In-situ DRIFTS revealed that KCl poisoning primarily suppresses the SCR reaction by occupying acid sites and reducing NH3 adsorption. The abundant acid sites of CeSn/ZrP can ensure that the catalyst retains a certain NH 3 adsorption capacity under high KCl loading.
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2025
·
IF 2.9
Yulong Deng,Jiacheng Zheng,Wenting Chen,Xu Wang,Chengliao Deng,Xiaoming Cai,Jinming Cai,Honglin Tan
NH3 selective catalytic reduction (SCR) is a promising method for NOx removal, but its low-temperature effectiveness and narrow operating window limit industrial use. This study demonstrates, through DFT calculations and experimental validation, that Fe-doped CoMn2O4 (CoFe0.1Mn1.9O4) catalysts can effectively enhance catalytic activity. Through the in-depth study of NH3-SCR, it was found that the NH3 adsorption on the catalyst surface might be significantly enhanced by the doping of Fe (Eads = −1.29 eV → −1.42 eV), and it was also further demonstrated that the NH3 had a better adsorption energy on the surface of the CoFe0.1Mn1.9O4 catalyst through the electron difference density (EDD) and partial density of states (PDOS). In addition to this, the CoFe0.1Mn1.9O4 catalyst not only reduces the first step of the dehydrogenation reaction of NH3 (Eα = 0.86 eV → 0.83 eV), but also lowers the energy barrier of the NH3-SCR (Eα = 1.11 eV → 0.86 eV). All these calculations demonstrate that Fe doping has the potential to significantly enhance catalytic performance. CoMn2O4 and Fe-doped CoMn2O4 (CoFe0.02Mn1.98O4) catalysts were synthesized using sol–gel and impregnation techniques, respectively. Through characterization and performance testing, CoFe0.02Mn1.98O4 is found to exhibit a more efficient NOx conversion (87% at 250 °C), and its N2 selectivity is also slightly improved (64%), which matches with the calculation results. In this study, a method to improve the denitrification efficiency of CoMn2O4 spinel catalysts was proposed, which provides a new idea for the development of CoMn2O4 catalysts.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2018
·
IF 2.829
Mingjuan Han,Ying Li,Zheng Gu,Huali Shi,Chong Chen,Qiang Wang,Hui Wan,Guofeng Guan
A novel functionalized MOF heterogeneous catalyst (MIL-101(Cr) @MBIAILs), 2-Mercaptobenzimidazole ILs with electron-rich SH groups immobilized onto the surface of the well-defined MIL-101(Cr) frameworks, was constructed and fabricated by the S Cr coordination bond on the basis of the facile post-synthetic modification strategy. The heterogeneous catalyst was measured by XRD , FTIR, SEM, TEM , TGA , EA and N 2 adsorption–desorption, and the catalytic behavior of the catalyst was assessed by the esterification about oleic acid and methanol as a model reaction. The results showed that MBIAILs have been successfully immobilized onto the surface of MIL-101(Cr) frameworks by S Cr coordinate bonds. More importantly, the conversion of oleic acid just decreased from 91.0% to 82.1% when the catalyst had been reused six times. This exhibited the prepared catalyst had superior catalytic behavior and excellent reusability.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2023
·
IF 5.4
Luyao Jin,Xintao Xu,Yanghui Wang,Jiaying Li,Kaihao Fan,Bo Hu,Yi Shen,Xuesong Liu
A series of MnO x /TiO 2 based NO x reduction catalyst was prepared by excessive impregnation method. The catalyst was modified by Ce, W and oxidizing agent H 2 O 2 . Mn-Ce/Ti-H and Mn-Ce-W/Ti-H catalysts exhibit the best low temperature activity (nearly 80% NO x conversion at 155–325 °C) and the widest active temperature range (nearly 80% NO x conversion at 180–420 °C), respectively. Property and structure of the modified catalyst were characterized by XRD, TEM, XPS, H 2 -TPR, NH 3 -TPD, etc. It is found that oxidizing agent H 2 O 2 , as well as the high dispersion and specific surface area, can increase the amount of Mn 4+ , Ce 3+ and active oxygen sites on catalyst surface, and the synergistic interaction between Mn and Ce facilitated redox process of the catalysts. These can improve the low temperature activity of the catalyst by facilitating “fast SCR” reaction. The addition of W increased acidity of the catalyst and improved high temperature catalytic activity of the catalyst.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2016
·
IF 2.628
Jixing Liu,Jian Liu,Zhen Zhao,Weiyu Song,Yuechang Wei,Aijun Duan,Guiyuan Jiang
A series of meso-microporous copper-supporting chabazite molecular sieve (Cu-SAPO-34) catalysts with excellent performance in low-temperature ammonia selective catalytic reduction (NH 3 -SCR) have been synthesized via a one-pot hydrothermal crystallization method. The physicochemical properties of the catalysts were characterized by scanning electron microscopy, transmission electron microscopy , N 2 adsorption-desorption measurements, X-ray diffraction, 27 Al magic angle spinning nuclear magnetic resonance , diffuse reflectance ultraviolet-visible spectroscopy, inductively coupled plasma-atomic emission spectroscopy, X-ray photoelectron spectroscopy , temperature-programmed reduction measurements, and electron paramagnetic resonance analysis. The formation of micro-mesopores in the Cu-SAPO-34 catalysts decreases diffusion resistance and greatly improves the accessibility of reactants to catalytic active sites. The main active sites for NH 3 -SCR reaction are the isolated Cu 2+ species displaced into the ellipsoidal cavity of the Cu-SAPO-34 catalysts.
研究领域:
材料化学
·
环境催化
·
多孔材料
·
工业催化
·
能源与环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Yijun Xue,Wei Sun,Qian Wang,Limei Cao,Ji Yang
MOFs (metal-organic frameworks) are stable materials with both organic and inorganic pores, and possess high surface area fascinating structures. Owing to the unique octahedral of aluminum center and strong Al–O bonds, Al-based MOFs show excellent thermal stability. In this paper, MIL-96(Al) is proved to be effective at dispersing Pt particles evenly and sparsely as it is employed as catalyst support. MIL-96(Al) is synthesized via a water based route and different contents of Pt particles are directly deposited on the surface of MIL-96 in one step by hydrothermal method to prepare Pt X MIL-96 (x represents Pt content) catalysts. The catalyst are sprayed evenly on carbon paper, with Pt content of 0.03%, 0.11%, 0.27% and 0.41%, respectively, and are applied in a gas diffusion reactor with snakelike flow field for low temperature H 2 -SCR. For Pt 5 MIL-96/CP, the NO removal efficiency can reach up to 100% at 60 °C. Electron transfer between Pt and MIL-96 is observed via X-ray photoelectron spectron (XPS). It reveals that the deposited Pt is in metallic state. Meanwhile, the electronic structure of MIL-96 is kept intact in the process of Pt depositing. The excellent performance of Pt 5 MIL-96/CP catalyst strongly suggests its potential application.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）