CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Renhui Ling,Mingxing Li,Xin Li,Laihuan Pei,Xiaoyan Luo,Congmin Wang
MOFs have high adsorption performance of ammonia (NH 3 ) because of its porosity and abundant coordination sites, especially MOFs containing carboxylic acid ligands have emerged as effect NH 3 adsorbents. But, it’s troublous for reversible ammonia adsorption for the strong metal-NH 3 coordination or the collapse of adsorbents. [MEDTA] 2- is a very stable and classic carboxylic acid-containing complex, but there was no relevant report. Therefore, this work carried out the design and synthesis of PVIm-R8-MEDTA based on the use of the coordination structure of [MEDTA] 2- and the stability of PILs’ skeleton. The characterization indicated the [MEDTA] 2- could be introduced into PILs successfully for the hydrogen bonding interactions with the imidazolium cation, and the obtained PVIm-R8-MEDTA presented enhanced NH 3 capacity (10.4–14.7 mmol/g) than their precursor PVIm-R8-Br (7.8 mmol/g). The mechanism of NH 3 adsorption was proposed by DFT calculation, spectroscopic method, and the calorimetric test, it indicated the NH 3 was fixed by imdazolium cation through hydrogen bonding and inserted into two of the carboxylate and metal bonds of [MEDTA] 2- . Because of the multi-meshing coordination of [EDTA] 4- and metal ions, the disconnected carboxylate ions could easily coordinate with metal ions again and repair the chelating structure of [MEDTA] 2- , which caused the ammonia easily be desorbed. In the process of gas adsorption, there was no bonding breakage of the skeleton of PILs, which helped the PVIm-R8-MEDTA be recovered under moisture and NH 3 atmosphere. Thanks for the designability of PILs, such as the cationic structure, structure and size of cross-linking agent, the choice of complex anion and so on, it provides a new design idea and theoretical basis for efficient and reversible ammonia adsorption materials.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2020
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IF 3.442
Li Wang,Junbo Wang,Xiaona Liu,Yaxin Chen,Heping Cheng,Yabin Wu,Hui Peng,Zhen Ma
An FeCeO x solid solution with an Fe/Ce molar ratio of 1 was obtained via a modified sol-gel method. The promotional effect of Fe 3+ ions in the lattice of cubic CeO 2 for catalytic reduction of NO with NH 3 was studied. The NO conversion over the FeCeO x catalyst was obviously higher than those over CeO 2 and Fe 2 O 3 catalysts. FeCeO x was characterized by using XRD , TEM, and XANES , etc. The experimental results revealed that Fe substituted Ce in CeO 2 to form an Fe–O–Ce solid solution with high activity for catalytic reduction of NO. The atomic and electric structures of the FeCeO x catalyst were studied to explain the enhanced catalytic activity.
研究领域:
材料科学
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环境催化
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2021
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IF 9.028
Guangzhi He,Meng Gao,Yue Peng,Yunbo Yu,Wenpo Shan,Hong He
Mn-based oxides exhibit outstanding low-temperature activity for the selective catalytic reduction of NOx with NH3 (NH3-SCR) compared with other catalysts. However, the underlying principle responsible for the excellent low-temperature activity is not yet clear. Here, the atomic-level mechanism and activity-limiting factor in the NH3-SCR process over Mn-, Fe-, and Ce-based oxide catalysts are elucidated by a combination of first-principles calculations and experimental measurements. We found that the superior oxidative dehydrogenation performance toward NH3 of Mn-based catalysts reduces the energy barriers for the activation of NH3 and the formation of the key intermediate NH2NO, which is the rate-determining step in NH3-SCR over these oxide catalysts. The findings of this study advance the understanding of the working principle of Mn-based SCR catalysts and provide a fundamental basis for the development of future generation SCR catalysts with excellent low-temperature activity.
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2025
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IF 5.3
Yuwan Zhu,Guangquan Wang,Kai Zong,Dongshun Deng
NH3 has attracted increasing attention as a fundamental material and promising hydrogen carrier. The uptake of NH3 from NH3-containing exhausted gas presents economic and environmental issues. In this study, [MEA][SCN] was paired with glycerol, acetamide, formamide, phenol (PhOH), ethylene glycol, urea, glycerolformal, or 1,3-dimethyl-2-imidazolidinone to construct deep eutectic solvents (DESs) for effective NH3 absorption and NH3/CO2 separation investigation. All of the [MEA][SCN]-based DESs exhibited good NH3 absorption and separation performance. Notably, [MEA][SCN]-PhOH (1:1) realized an atmospheric capacity of 0.2459 g of NH3·g–1 DES and NH3/CO2 selectivity of 194.53 at 303.15 K. Based on the experimental data, a new process for NH3 recovery from melamine tail gas using [MEA][SCN]-PhOH (1:1) (DES-M) was developed and simulated from operational parameters optimization, heat exchange network design, and economic evaluation. DES-M can recycle NH3 with purity of 99.6% and save 82.01% utility costs compared to the water scrubbing method. The heat integration network design in DES-M reduces 66.94% low-pressure steam and 9.00% separation costs. Specially, the optimized DES-M can exceed 59% after-tax rate of return using renewable energy.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
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2020
·Vol. 10
·期 11
·2170
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IF 4.324
Jialing Chen,Gang Peng,Tingyu Liang,Wenbo Zhang,Wei Zheng,Haoran Zhao,Li Guo,Xiaoqin Wu
The NH3-SCR activities and hydrothermal stabilities of fivexCu/MCM-22 zeolites with different Cu loadings (x= 2–10 wt%) prepared by incipient wetness impregnation method were systematically investigated. The physicochemical properties ofxCu/MCM-22 zeolites were analyzed by XRD, nitrogen physisorption, ICP-AES, SEM, NH3-TPD, UV-vis, H2-TPR and XPS experiments. The Cu species existing inxCu/MCM-22 are mainly isolated Cu2+, CuOxand unreducible copper species. The concentrations of both isolated Cu2+and CuOxspecies inxCu/MCM-22 increase with Cu contents, but the increment of CuOxspecies is more distinct, especially in high Cu loadings (>4 wt%). NH3-SCR experimental results demonstrated that the activity ofxCu/MCM-22 is sensitive to Cu content at low Cu loadings (≤4 wt%). When the Cu loading exceeds 4 wt%, the NH3-SCR activity ofxCu/MCM-22 is irrelevant to Cu content due to the severe pore blockage effects caused by aggregated CuOxspecies. Among the fivexCu/MCM-22 zeolites, 4Cu/MCM-22 with moderate Cu content has the best NH3-SCR performance, which displays higher than 80% NOxconversions in a wide temperature window (160–430 °C). Furthermore, the hydrothermal aging experiments (xCu/MCM-22 was treated at 750 °C for 10 h under 10% water vapor atmosphere) illustrated that all thexCu/MCM-22 zeolites exhibit high hydrothermal stability in NH3-SCR reactions.Keywords:Cu/MCM-22;NH3-SCR;Cu loading;hydrothermal aging
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Fanfan Yan,Guowen Shen,Xi Yang,Tianjiao Qi,Jie Sun,Xinghua Li,Mingtao Zhang
Developing of novel chemiresistive gas sensing materials with desired unique gas chemisorption properties is of great important. In this work, motivated by the special electronic structure, Ag 3 PO 4 semiconductor is systematically investigated as gas sensing material for the first time. Encouragingly, the Ag 3 PO 4 nanoparticles based gas sensors exhibit high selectivity to NH 3 at near room temperature of 50 °C with negligible responses to the other gases (including H 2 , CO, ethanol, acetone, NO 2 and SO 2 ). Furthermore, the responses decreased with the increase of operating temperature from 50 to 100 °C, indicating the superior NH 3 sensing activity. The in-situ infrared characterization and theoretical calculations reveal that the lone pair of NH 3 coordinate with the superficial silver atoms of Ag 3 PO 4 accompanied with strong adsorption energy , efficient quantities electron migration and thermodynamic favorable, explained the origin of the high selectivity. Our work indicates that Ag 3 PO 4 based materials are very promising low operating temperature and highly selective NH 3 -sensing materials.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2019
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IF 7.149
Fei Wang,Zhibo Xie,Jinsheng Liang,Baizeng Fang,Yu’ang Piao,Ming Hao,Zishuo Wang
Low temperature NH3 selective catalytic reduction (NH3-SCR) technology is an efficient and economical strategy for cutting NOx emissions from power-generating equipment. In this study, a novel and highly efficient NH3-SCR catalyst, tourmaline-modified FeMnTiOx is presented, which was synthesized by a simple one-step sol–gel method. We found that the amount of tourmaline has an important impact on the catalytic performance of the modified FeMnTiOx-based catalysts, and the NOx conversion exceeded 80% from 160 to 380 °C with the addition of 5 wt % tourmaline. Compared with the pure FeMnTiOx, the catalytic efficiency at a temperature below 100 °C was increased by nearly 18.9%, and the operation temperature window was broadened significantly. The enhanced catalytic performance of the FeMnTiOx catalyst was mainly attributed to the small spherical nanoparticles structure around the tourmaline powders, resulting in the increased content of Mn3+, Mn4+, and chemical oxygen on the catalytic surface. These as-developed tourmaline-modified FeMnTiOx materials have been demonstrated to be promising as a new type highly efficient low temperature NH3-SCR catalyst.
研究领域:
环境科学
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催化材料
·
能源工程
✓ 已验证
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
·
IF 3.375
Siqian Zhang,Cheng Zhang,Qiang Wang,Wha-Seung Ahn
A series of ZSM-5 catalysts were synthesized using fly ash from power plants and red mud from aluminum production in different weight ratios. The ZSM-5 was subsequently coimpregnated with Co and Mn and tested for the low-temperature selective catalytic reduction of NOx by NH3 (NH3-SCR). These catalysts were characterized by XRD, N2-adsorption isotherms, SEM, XPS, and H2-TPR. Among all the prepared catalysts, 5 wt % Co 10 wt % Mn/ZSM-5 had shown the best catalytic activity, with 98.8% conversion of NOx and 90.7% selectivity toward N2 at 150 °C. This is comparable to the performance of a similar ZSM-5 catalyst prepared using chemical reagents. The high ratio of Mn4+/(Mn4+ + Mn3+ + Mn2+) in the catalyst improved the NOx conversion, whereas the moderate redox property imparted by Co3+ led to high N2 selectivity. This catalyst also showed strong resistance against poisoning in 100 ppm SO2 and 5% H2O. This work demonstrates that effective NOx removal treatment with high N2 selectivity and sufficient stability for either cement plants or incinerators can be achieved by using a porous catalyst/support material produced from industrial solid wastes.
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
Catalysts
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2020
·Vol. 10
·期 3
·311
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IF 3.52
Jing Shao,Shuyuan Cheng,Zhaoxu Li,Bichun Huang
A ZSM-5 zeolite with a hierarchical pore structure was synthesized by the desilication-recrystallization method using tetraethyl ammonium hydroxide (TEAOH) and cetyltrimethylammonium bromide (CTAB) as the desilication and structure-directing agents, respectively. The MnOx/ZSM-5 catalyst was synthesized by the ethanol dispersion method and applied for the low-temperature selective catalytic reduction of NOxwith NH3. The results showed that NOxconversion of the hierarchical MnOx/ZSM-5 catalyst could reach 100% at about 120 °C and could be maintained in the temperature range of 120–240 °C with N2selectivity over 90%. Furthermore, the hierarchical MnOx/ZSM-5catalyst presented better SO2resistance performance than the traditional catalyst in the presence of 100 ppm SO2at 120 °C. XRD, SEM, TEM, XPS, BET, NH3-TPD, and TG were applied to characterize the structural properties of the MnOx/ZSM-5 catalysts. These results showed that the MnOx/ZSM-5 catalyst had micropores (0.78 nm) and mesopores (3.2 nm) leading to a larger specific surface area, which improved the mass transfer of reactants and products while reducing the formation of sulfates. The better catalytic performance over hierarchical MnOx/ZSM-5 catalyst could be attributed to the higher concentration of Mn4+and chemisorbed oxygen species and higher surface acidity. The improved SO2resistance was related to the catalyst’s hierarchical pore structure.Keywords:hierarchical pore structure;MnOx/ZSM-5;NH3-SCR;SO2resistance
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2023
·
IF 3.8
Xudong Liu,Fengyuan Liu,Junqi Li,Yuanpei Lan,Jian Yang,Arun Murali,Chaoyi Chen,Wei Zhang
To accurately evaluate the phase effects of MnO x in Mn-Ce catalysts towards to low temperature NO x removal performance with NH 3 , MnCO 3 @CeCO 3 OH was synthesized firstly and decomposed to MnO 2 @CeO 2 , Mn 2 O 3 @CeO 2 and Mn 3 O 4 @CeO 2 with similar size and morphology, this will avoid the influence of size and morphology on the experimental results. Experimental results show that the MnO 2 @CeO 2 exhibiting the best NO conversion ratio, which achieved nearly 96.5 % at a low temperature of 150 °C, and the catalytic performance order of MnO x @CeO 2 is determined as: MnO 2 @CeO 2 > Mn 2 O 3 @CeO 2 > Mn 3 O 4 @CeO 2 below 200 °C, and MnO 2 @CeO 2 > Mn 2 O 3 @CeO 2 ≈Mn 3 O 4 @CeO 2 at range of 200 –400 °C. But the N 2 selectivity of Mn 2 O 3 @CeO 2 reaches 96 % at 100 °C which was higher than that of MnO 2 @CeO 2 and Mn 3 O 4 @CeO 2 . Characterizations including BET, XRD, SEM, H 2 -TPR, NH 3 -TPD and FTIR show that MnO 2 @CeO 2 has maximum specific surface area, a stronger redox ability, and more surface acid sites.
研究领域:
催化材料
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Xin Guo,Zhiyong Ding,Na Kang,Liu Yang,Yuanjiang Wang,Cheng Zhang,Zhaoqiang Li,Tiantian Zhang,Yan Wang,Yu Wang,Hao Qu
The zeolite-based catalyst is a promising option for the selective catalytic reduction (SCR) of nitrogen oxides (NO x ) due to its low toxicity. However, the challenge lies in its low-temperature activity. This study developed a multi-component catalytic system consisting of Ce/Mn/Cu-loaded Beta zeolite to reduce NO x . With fixed contents of Cu and Mn, we investigated the NH 3 -SCR process and the mechanism of action of the rare-earth species (i.e., Ce) in the system. Upon optimization of the content of Ce, the Ce/Mn/Cu-loaded Beta zeolite demonstrated enhanced low-temperature activity compared to samples loaded with Cu or Cu/Mn in the temperature range of 150–250 °C. When Ce was loaded in an appropriate proportion, it regulated the oxidation state of Cu, optimizing active adsorption species for NO and strengthening the strength of Brønsted acid sites in the catalyst. These synergetic effects led to improved NH 3 -SCR catalytic performance. This study can contribute to a better understanding of multiple metal-loaded zeolites in the NH 3 -SCR process and inform future design of Beta-type catalysts.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Qinyu Zhou,Chong Tan,Tianfa Tang,Yu Wang,Siyuan Li,Meilin Tao,Hongliang Zhang,Liu Yang,Changjin Tang
The occurrence of NH 3 over-oxidation represents one intractable challenge for the effective application of NH 3 -SCR technology. Herein, a rational NO x activation strategy was innovatively proposed to counteract NH 3 over-oxidation during high temperature NH 3 -SCR. As a proof of concept, the hybrid catalyst of CeO 2 -ZSM-5 was explored. It was shown that the activity of CeO 2 in NH 3 -SCR was profoundly improved via physically mixing with ZSM-5, achieving more than 85 % NO at 500 °C, in sharp contrast to the negative NO conversion present for pristine CeO 2 . Comprehensive characterizations from NH 3 -TPD, NO-TPD and in situ DRIFTS verified the negligible modification of NH 3 oxidation but significant alteration of surface NO x . Due to the facile NO x activation, the reaction of NH 3 + NO x overwhelms that of NH 3 + O 2 , leading to the obtainment of excellent high temperature NH 3 -SCR performance. The novel strategy reported here is expected to provide valuable guidance for designing NH 3 -SCR catalysts with superior high temperature performance.
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
危险品化学品经营许可证（带存储）