CHINESE JOURNAL OF CATALYSIS
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2025
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IF 17.7
Ye Wang,Pan Gao,Dan Zhao,Tongrui Liu,Sitong Zhou,Miao Yang,Shiping Liu,Bing Li,Yida Zhou,Wenhao Cui,Guangjin Hou,Peng Tian,Zhongmin Liu
Silicoaluminophosphate (SAPO) molecular sieves possess diverse architectures and exceptional high-temperature hydrothermal stability, rendering them important acid catalysts. However, enhancing acid concentration of certain SAPO materials remains challenging, which limits their catalytic applications. Here, we report the synthesis of a series of SAPO materials using a developed SAPO precursor plus dual template (SPDT) strategy. A variety of SAPO materials characterized by high silica content and enhanced acidity, such as SAPO-34/56 intergrowths, SAPO-56, and SAPO-17, have been synthesized and thoroughly characterized using various techniques including integrated differential phase-contrast scanning transmission electron microscopy, two-dimensional solid-state nuclear magnetic resonance spectroscopy, and continuous rotation electron diffraction. The use of silica-enriched SAPO precursor combined with the flexible selection of the second template enables the crystalline phase regulation and improves the Si atoms incorporation into the framework. Notably, the synthesized SAPO-17 with abundant Si(4Al) species and unprecedentedly high acid density exhibits exceptional DeNO x activity after Cu loading, with NO x conversion exceeding 90% at 175–700 °C. This outstanding performance can be attributed to the unique ERI structure and the increased acidity of SAPO-17. This work not only presents an effective method for synthesizing SAPO molecular sieves with enhanced acidity but also offers a new perspective for expanding the active temperature range of the ammonia selective catalytic reduction reaction.
研究领域:
材料化学
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催化化学
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无机非金属材料
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环境催化
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分子筛科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2021
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IF 6.707
Xiaofeng Wang,Zhe Zhao,Yang Xu,Qingbo Li
A series of 3DOM-Mn x Ce y Ti z catalysts with three-dimensionally ordered macroporous (3DOM) structure were synthesized by a soft template method. The high SCR activity of the 3DOM-Mn 3 Ce 1 catalyst at low temperature was owing to the excellent redox ability and rich Lewis and Brønsted acid sites of the catalysts, which were beneficial to improve the catalytic activity. However, the strong oxidizability of MnO x resulted in the nonselective oxidation of NH 3 and generation of N 2 O, decreasing the N 2 selectivity. After addition of Ti, the redox capacity of the 3DOM-Mn 3 Ce 1 Ti 1 catalyst decreased, and the NH 3 were strongly adsorbed on the acid sites, which enhanced the N 2 selectivity with a broadened temperature window of 240–440 °C and a high GHSV of 120000 h −1 . Furthermore, both the 3DOM-Mn 3 Ce 1 and 3DOM-Mn 3 Ce 1 Ti 1 catalysts showed remarkable tolerance of H 2 O. Finally, through in situ DRIFT analysis, the Langmuir-Hinshelwood (L-H) mechanism was confirmed as the dominant reaction pathway over the 3DOM-Mn 3 Ce 1 Ti 1 catalyst.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2025
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IF 3.9
Jinfeng Chen,Qingze Zhang,Yuanhong Zhong,Zhaoying Wang,Yakun Guo,Ming Sun,Lin Yu
To address the limitations of molecular sieves and metal oxides in the NH3-SCR of NOx, we synthesized a novel hybrid catalyst by integrating FeNbCe metal oxides with Cu-SSZ-13. The FeNbCe comodification significantly enhanced the low-temperature performance and sulfur resistance of Cu-SSZ-13 while maintaining 100% N2 selectivity across a broad activity window. The incorporation of Fe, Nb, and Ce reduced weak-acid and Lewis-acid sites while increasing strong Brønsted-acid sites, crucial for catalytic activity. The FeNbCe/Cu-SSZ-13 catalyst exhibited an enhanced surface oxygen content and redox capacity, promoting the “fast SCR” pathway and improving N2 selectivity at low temperatures. The FeNbCe oxides synergistically reacted with SO2, protecting Cu2+ active sites from sulfur poisoning and maintaining 100% NOx conversion for 4 h after SO2 introduction, maintaining 85% within 24 h. In situ DRIFTS characterization confirmed the dominance of the Langmuir-Hinshelwood (L-H) mechanism. The FeNbCe modification represents a significant advancement in the field of NH3–SCR catalysis, offering a practical and effective solution to enhance the performance of Cu-SSZ-13 while addressing key challenges such as sulfur resistance and low-temperature activity.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
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IF 16.744
Chengzhi Wang,Fengyu Gao,Songjin Ko,Hengheng Liu,Honghong Yi,Xiaolong Tang
The presence of SO 2 in industrial flue gases will cause permanent deactivation of the catalyst active centre. Therefore, an effective method to improve the SO 2 resistance of manganese-based catalysts at low temperatures is urgently needed. In this work, a hierarchical porous nanowire structure catalyst was designed by the in situ self-assembly method to inhibit SO 2 adsorption. This hierarchical porous nanowire aerogel catalyst with great BET surface area and surface acidity exhibited NOx conversion above 90% at 100–400 °C. Notably, the NOx conversion of the MnCe-N catalyst was almost not inhibited by SO 2 (250 ppm) compared to the 33% decrease of the MnCe-P catalyst. On the MnCe-P catalyst, SO 2 has strong competitive adsorption with NH 3 and NO, and the stronger adsorption capacity of SO 2 inhibits the adsorption activation of the reaction gas and hinders the reaction proceeding through the L-H mechanism. Meanwhile, a large quantity of sulfate is formed on the catalyst surface, which prevents the active centre to participate in the redox reaction. The structure of nanowires enhances the number of acid sites, facilitates the adsorption and activation of NH 3 , and effectively inhibits the adsorption of SO 2 on the MnCe-N catalyst. Fewer sulfate species are generated and difficult to deposit and aggregate on the catalyst surface, as a result, the active centre is less affected by sulfate species. The stable adsorption of NH 3 -related species ensures reliable reaction on MnCe-N through the E-R mechanism. This work emphasizes the importance of hierarchically porous structures in improving the NH 3 -SCR performance and SO 2 resistance of monolithic catalysts, and provides new insights into the design of highly efficient and stable catalytic materials.
研究领域:
催化
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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
Catalysis Science & Technology
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2024
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IF 4.4
Zhicheng Xu,Jin Xiong,Yuran Li,Junxiang Guo,Bin Wang,Tingyu Zhu
For industrial flue gas purification at medium and low temperatures, it is highly necessary to promote the denitrification activity of V-based catalysts in a SO2 atmosphere. Transition metals (Ce, Co, Fe, and Mn) are used to modify V/Ti catalysts to improve SO2 resistance with ammonium bisulfate deposition on the catalysts. Sulfation on Ce with less ammonium bisulfate deposition considerably improves the SO2 resistance of V1Ce5/Ti, and stable sulfation on TiO2 promoted by Co provides additional Brønsted acid sites for V1Co5/Ti to reduce the deactivation. Serious sulfation on V1Mn5/Ti with large ammonium bisulfate deposition on V1Fe5/Ti causes deeper deactivation. The formation mechanism of ammonium bisulfate on active metal sites and TiO2 carriers has been clarified. SO2 is adsorbed on V sites and transition metal sites followed by oxidation and ammoniation or adsorbed on TiO2 carriers followed by ammoniation and oxidation. The first pathway is more dominant than the second pathway in the presence of O2 with the co-oxidation of SO2 by O2 and lattice oxygen. The initial formation temperature and stable temperature of dominant intermediates were determined by in situ DRIFTS. SO2 adsorbed on TiO2 carriers is oxidized by V sites above 170 °C to form a tridentate sulfate, while SO2 adsorbed on transition metal sites is initially oxidized by transition metal sites above 50 °C to form monodentate and bidentate sulfates, as well as competitively oxidized by V sites above 170 °C to form tridentate sulfates. The selective adsorption of SO2 on transition metal sites or TiO2 carriers and the competitive oxidation of SO2 by transition metal sites and V sites provide a synergistic effect between V sites and transition metal sites to reduce ammonium sulfate deposition and release more active sites. These findings provide theoretical guidance to design and prepare V-based catalysts with high denitrification activity in the presence of SO2.
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
ACS Applied Materials & Interfaces
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2025
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IF 8.2
Kaiting Chen,Qingwei Li,Xinyu Han,Cheng Rao,Xiangguang Yang,Yibo Zhang
Developing efficient low-temperature selective catalytic reduction (CO-SCR) catalysts remains a key challenge in reducing nitrogen oxide (NOx) emissions. Here, we report a photothermal-enhanced Rh–Mn/CoAlOx heterostructure catalyst that achieves excellent NO conversion (more than 90% at 140 °C) and N2 selectivity (>80%) under visible to infrared light irradiation. By integration of highly dispersed Rh units with Mn clusters onto a hydrotalcite-derived CoAlOx support, the catalyst exhibits synergistic light absorption and dynamic lattice oxygen migration capabilities. Through combined analysis using in situ DRIFTS, XAFS, XPS, EPR, and other techniques, we reveal that Mn doping induces numerous oxygen vacancies and promotes electron transfer between Rh and Mn, facilitating lattice oxygen activation via a mechanism similar to the Mars-van Krevelen mechanism. Light exposure reduces the activation energy and, according to Arrhenius analysis and NO-TPD results, accelerates the decomposition of nitrate intermediates and enhances the conversion rate of nitrous oxide to N2. Density functional theory (DFT) calculations confirm that N2O is more likely to be generated at the Rh–Mn interface, demonstrating its enhanced low-temperature activation ability for NO. This study innovatively enhances the catalytic performance of CO-SCR using light, providing a sustainable method for reducing low-energy NOx emissions.
研究领域:
催化
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环境化学
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材料科学
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物理化学
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纳米技术
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化学反应工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Qin Wu,Chi Fan,Ya Wang,Xiaoping Chen,Guimin Wang,Zhengxing Qin,Svetlana Mintova,Junhua Li,Jianjun Chen
The reduction of NO x emission during the cold start period of diesel vehicles requires special attention in accordance with the emission regulations. In this work, the direct incorporation of cerium and copper in SAPO-18 catalyst with AEI type framework structure (CuCe-SAPO-18) resulting in a substantial enhancement of the performance in the low-temperature NH 3 -SCR reaction (<200 ℃). A small amount of cerium (0.13–0.31 wt%) broadened the reaction temperature range of use and increased the hydrothermal stability of the catalyst considerably. The cerium species was introduced in the ion-exchange sites of Cu-SAPO-18 in the form of Ce 3+ ions even with high loading (3.15 wt%). The Ce 3+ ions were found to affect the distribution of silicon and aluminum atom coordination ( 29 Si NMR, 27 Al MAS NMR) in the AEI-type skeleton structure leading to an increase of both the amount of active Cu 2+ species and the acidity of the CuCe-SAPO-18 catalysts that are beneficial for the NH 3 -SCR reaction.
研究领域:
催化化学
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环境科学
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材料化学
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大气污染控制
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无机固体化学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Rong Mu,Zepeng Lv,Shaolong Li,Jilin He,Jianxun Song
Spent SCR catalysts, classified as high-risk solid waste, are produced in large quantities and are rich in critical metals such as Ti, V, W, and Mo, making them highly valuable for recycling. This study proposes a novel process combining hydrogen-rich reduction with hydrometallurgical leaching for the recycling of spent SCR catalysts. Thermodynamic calculations and experimental validation showed that the proposed process converts high-value oxides (TiO 2 , V 2 O 5 , WO 3 and MoO 3 ) into multicomponent carbides under a CH 4 –H 2 atmosphere. The effects of temperature, reaction time, and Fe 2 O 3 additives on phase transformation were systematically investigated. To remove residual impurities that were not reduced in the high-temperature reaction, selective acid and alkaline leaching were employed. Owing to their chemical stability, the formed multicomponent carbides remained inert during leaching. The optimized recycling process involved the addition of 8 wt% Fe 2 O 3 to the catalyst, followed by thermal treatment at 1400 °C for 3 h. Impurities were removed using 0.5 mol·L⁻¹ HCl and 1 mol·L⁻¹ NaOH solutions. The final product exhibited a face-centered cubic structure with a uniform distribution of Ti, V, W, and Mo and an average lattice parameter of 4.3012 Å, as revealed through Rietveld refinement. Impurities such as Fe, Al, Si, Ca, and S were effectively removed. The product can be used in fields such as conductive materials and hard alloys. This study provides a promising route for the high-value utilization of spent SCR catalysts.
研究领域:
环境工程
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冶金学
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材料科学
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化学工程
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废弃物回收
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
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2015
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IF 2.002
Lei Chen,Zhichun Si,Xiaodong Wu,Duan Weng,Zhenwei Wu
A MnO x –NbO x –CeO 2 catalyst for low temperature selective catalytic reduction (SCR) of NO x with NH 3 was prepared by a sol–gel method, and characterized by NH 3 –NO/NO 2 SCR catalytic activity , NO/NH 3 oxidation activity, NO x /NH 3 TPD , XRD , BET, H 2 -TPR and in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). The results indicate that the MnO x –NbO x –CeO 2 catalyst shows excellent low temperature NH 3 -SCR activity in the temperature range of 150–300°C. Water vapor inhibits the low temperature activity of the catalyst in standard SCR due to the inhibition of NO x adsorption. As the NO 2 content increases in the feed, water vapor does not affect the activity in NO 2 SCR. Meanwhile, water vapor significantly enhances the N 2 selectivity of the fresh and the aged catalysts due to its inhibition of the decomposition of NH 4 NO 3 into N 2 O.
研究领域:
环境催化
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大气污染控制
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材料化学
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表面科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Xin Yang,Kaijie Liu,Xinyu Han,Jianheng Xu,Mengyao Bian,Daying Zheng,Haijiao Xie,Yibo Zhang,Xiangguang Yang
It is essential to develop the catalyst for NH 3 -SCR with excellent performance at ultra-low temperature (≤150 °C), and resource recycling is another important part of environmental protection. Based on the principle of environmental friendliness, the LiMn 2 O 4 , one of the waste battery cathode materials, was successfully modified into a novel high-value catalyst for ultra-low temperature NH 3 -SCR through hydrogen ion exchange and two-dimensional vanadic oxide modification. The optimized LiMn 2 O 4 -0.5V-10H catalyst performed the best balance of NO x conversion and N 2 selectivity , with activity reaching 96 % at 150 °C and N 2 selectivity exceeding 70 % at ultra-low temperature. Due to the unique three-dimensional network structural characteristics of LiMn 2 O 4 spinel, hydrogen exchange could exchange Li + from the lattice and increase surface acidity; and a small amount of two-dimensional vanadic oxide loading could appropriately regulate redox ability and increase acidic sites. The in-situ DRIFTS results still showed that the L-H and E-R mechanisms coexisted during the reaction. Moreover, combining first-principles calculations and in-situ DRIFTS, the dual modification of H and V could enhance the adsorption of NH 3 on the surface of LiMn 2 O 4 but weaken the adsorption of NO, and promote the decomposition of nitrites while inhibit the formation of surface nitrate species, which was the core reason for the improvement of N 2 selectivity. The modification mode in this work was simple and inexpensive, which provided a new idea for the high-value utilization of waste batteries and the design of NO x purification catalyst at ultra-low temperature.
研究领域:
环境科学
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催化
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
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2019
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IF 4.63
Li Cao,Xiaodong Wu,Ze Chen,Yue Ma,Ziran Ma,Rui Ran,Zhichun Si,Duan Weng,Baodong Wang
CeO 2 /WO 3 -TiO 2 (CeWTi) and Nb 2 O 5 -CeO 2 /WO 3 -TiO 2 (NbCeWTi) catalysts were prepared by a sol-gel precipitation method. Both the catalysts exhibit high selective catalytic reduction of NO x with NH 3 (NH 3 -SCR) activities at 270–500 °C. The sulfur tolerances of the catalysts were evaluated at 270 °C by adding H 2 O and SO 2 in the feeding gas and NbCeWTi exhibited a significantly improved resistance. The thermogravimetric (TG) and mass spectrographic (MS) results indicated that much less sulfates formed on NbCeWTi and existed mainly in the form of ammonium hydrogen sulfate species which protected Ce x+ active sites effectively from attacking of SO 2 . According to the results of temperature-programmed desorption of ammonia (NH 3 -TPD), H 2 temperature-programmed reduction (H 2 -TPR) and SO 2 oxidation , loading niobia on CeWTi inhibited the SO 2 oxidative adsorption and SO 3 production which basically reduced sulfur poisoning of the catalyst. Additionally, the niobia modification ensured the formation of nitrates from the competitive adsorption of SO 2 and hereby facilitated the nitrate SCR route based on the in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS).
研究领域:
催化
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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 CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Ning Luo,Fengyu Gao,Hengheng Liu,Tingkai Xiong,Jiajun Wen,Erhong Duan,Chengzhi Wang,Shunzheng Zhao,Honghong Yi,Xiaolong Tang
Developing effective and stable catalysts for low-temperature selective catalytic reduction (SCR) of NO x remains challenging. Herein, we constructed a hierarchical structure by loading CoMn 2 O 4 onto Ti-doped CeO 2 , that CoMn 2 O 4 /CeTiO x catalyst has shown superior deNO x activity (>95% at 100–225 °C), prominent reaction activation energy (28.8 ± 0.9 kJ mol −1 ) and outstanding stability (>75% at 100–200 °C within H 2 O and SO 2 ). The “low-temperature active sites” and “dual anti-poisoning sites” contribute to excellent activity and stability. Firstly, the hierarchical structure boosts generation of active metal-support interface, which is conducive to oxygen migration (including adsorbed oxygen (O ads ), lattice oxygen (O lat ) and oxygen vacancy (O v )) and metal charge transfer (Mn 2+/3+ +Ce 4+ ↔Mn 3+/4+ +Ce 3+ , Ti 4+ +Ce 3+ ↔Ce 4+ +Ti 3+ ). This is the key to breaking through the limits of catalytic activity stability. Secondly, enhanced surface acidity favors NH 3 adsorption and activation, which accelerates -NH 2 /-NH concatenate with NO x through Eley-Rideal mechanism to generate N 2 and H 2 O. Thirdly, the dual strong SO 2 affinity sites by Ti-induced CeO 2 crystal reconstruction retard the active center affected by the sulfate species, which contributes to striking stability. This work highlights the importance of design of isolated active sites to improve SO 2 and H 2 O endurance.
研究领域:
催化
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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
危险品化学品经营许可证（带存储）