JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2022
·Vol. 98
·期 2
·506-515
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IF 3.709
Cao Shuang,Zhang Haixiang,Wang Xueman,Peng Miquan,Huang Renhua,Hong Wei,Fu Hailu,Chen Xiongbo,Lin Zejian
In SCR denitrification technology, the conventional coprecipitation method has the disadvantages of high temperature and difficulty in controlling the precipitation rate. Various Ce x CuTiO 2 catalysts were synthesized using ice-melting (Ce x CuTi-Ice) and conventional coprecipitation (Ce x CuTi-Con) methods for the selective catalytic reduction (SCR) of NO with NH 3 . Ce 0.4 CuTi-Ice catalyst exhibited excellent catalytic activity among the Ce x CuTiO 2 catalysts, and 80% NO x conversion was achieved within a temperature range of 250–375 °C, exceeding that of Ce 0.4 CuTi-Con catalyst by 20%; in addition, N 2 selectivity was nearly 100%. To elucidate the release characteristics of the precursor solution during ice-melting synthesis, the changes of Cu and Ce concentrations in the solution were investigated by ICP-OES. The precursor solution was released at a slow rate via the ice-melting method, resulting in a large surface area, small crystallite sizes, and effective uniform nanoparticles with abundant active species and increased surface acidity. The promoted mechanism could be attributed to the enhanced oxidation of NO to NO 2 at low temperatures and the rapid reaction between NO species and coordinated NH 3 at high temperatures. © 2022 Society of Chemical Industry (SCI).
研究领域:
环境科学
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催化化学
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DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 84
·53622-53630
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IF 3.108
Changming Li,Hong Zeng,Pingle Liu,Jian Yu,Feng Guo,Guangwen Xu,Zhan-guo Zhang
The development of new routes for the utilization of red mud (RM) waste is very urgent due to its huge accumulation and potential environmental harm. By taking advantage of its Fe–Al–Si–Ti composition and excellent plasticity, we developed a ball milling and acid–base neutralization method to reuse the RM waste as Fe-based denitration catalysts. The resulting RM catalysts demonstrate excellent catalytic activity and stability with >90% NO conversion above 400 °C in the presence of SO2 and H2O, which is even much better than that of a commercial V–W–Ti catalyst. Characterization data reveal that our treatment eliminates poisonous alkaline metal elements and increases dispersion of RM particles, making the RM active for denitration reactions. The formation of ferric sulfate species with more reducible Fe3+/Fe2+ active sites by a SO2 activation method can further enhance the denitration activity. Moreover, NH3-TPD and in situ IR results demonstrate that the NH3-SCR reaction over the RM catalyst follows the Eley–Rideal mechanism at high temperature and the increased absorption of NH3 for alkaline metal-eliminated or SO2-activated samples accounts for its high DeNOx efficiency. The demonstrated feasibility for reusage of the RM as DeNOx catalyst has promising industrial prospects for its extremely low cost, no toxicity, and high efficiency.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2019
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IF 5.107
Yong Cai,Yong Luo,Guang-Wen Chu,Wei Wu,Xiao Yu,Bao-Chang Sun,Jian-Feng Chen
In view of the continuously stringent standard of nitrogen oxides (NO x ) emissions, developing new technologies for NO x removal or updating the existing NO x removal system is very urgent. This work introduces a novel technology for NO x removal in an RPB reactor by the combination of oxidation and enhanced absorption. Experimental results show that a rotating packed bed (RPB) reactor, having high gas-liquid mass transfer efficiency, is a more appropriate choice for NO x removal. Then a series system combining firstly a stirred tank reactor (STR) and secondly an RPB reactor, has been developed in order to oxidize more NO to NO 2 that is very soluble and enhances the subsequent absorption in the RPB reactor. The higher oxidation degree (~99%) was achieved with a sodium chlorite concentration of 0.10 mol L −1 and a liquid volume of 5.0 L in the STR. An absorbent containing sulfonated cobalt phthalocyanine (CoPcS) was employed in the RPB reactor to meet the demand of very efficient denitrification for a long-term running. Compared to the traditional urea/sodium chlorite composite absorbent in a single RPB system, the total NO x removal efficiency increased by approximately 30% through the absorbent containing CoPcS in a series system under the optimized conditions.
研究领域:
环境工程
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化学工程
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2019
·
IF 8.456
Zhenyu Wang,Yu Huang,Meijuan Chen,Xianjin Shi,Yufei Zhang,Junji Cao,Wingkei Ho,Shun Cheng Lee
The development of catalysts that effectively activate target pollutants and promote their complete conversion is an admirable objective in the environmental photocatalysis field. In this work, graphitic carbon nitride (g-C3N4) microtubes with tunable N-vacancy concentrations were controllably fabricated using an in situ soft-chemical method. The morphological evolution of g-C3N4, from the bulk to the porous tubular architecture, is discussed in detail with the aid of time-resolved hydrothermal experiments. We found that the NO removal ratio and apparent reaction rate constant of the g-C3N4 microtubes were 1.8 and 2.6 times higher than those of pristine g-C3N4, respectively. By combining detailed experimental characterization and density functional theory calculations, the effects of N-vacancies in the g-C3N4 microtubes on O2 and NO adsorption activation, electron capture, and electronic structure were systematically investigated. These results demonstrate that surface N-vacancies act as specific sites for the adsorption activation of reactants and photoinduced electron capture, while enhancing the light-absorbing capability of g-C3N4. Moreover, the porous wall structures of the as-prepared g-C3N4 microtubes facilitate the diffusion of reactants, and their tubular architectures favor the oriented transfer of charge carriers. The intermediates formed during photocatalytic NO removal processes were identified by in situ diffuse reflectance infrared Fourier transform spectroscopy, and different reaction pathways over pristine and N-deficient g-C3N4 are proposed. This study provides a feasible strategy for air pollution control over g-C3N4 by introducing N-vacancy and porous tubular architecture simultaneously.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2016
·
IF 2.628
Yanke Yu,Jinsheng Chen,Jinxiu Wang,Yanting Chen
A series of CuSO 4 /TiO 2 catalysts were prepared using a wet impregnation method. The activity of each sample in the selective catalytic reduction of NO by NH 3 (NH 3 -SCR) was determined. The effects of SO 2 and H 2 O, and their combined effect, on the activity were examined at 340 °C for 24 h. The catalysts were characterized using N 2 adsorption-desorption, X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed reduction of H 2 (H 2 -TPR), temperature-programmed desorption of NH 3 (NH 3 -TPD), and in situ diffuse-reflectance infrared Fourier-transform spectroscopy (DRIFTS). The CuSO 4 /TiO 2 catalysts had good activities, with low production of N 2 O above 340 °C. SO 2 or a combination of SO 2 and H 2 O had little effect on the activity, and H 2 O caused only a slight decrease in activity during the experimental period. The NH 3 -TPD and H 2 -TPR results showed that CuSO 4 increased the amounts of acid sites and adsorbed oxygen on the catalyst. In situ DRIFTS showed that the NH 3 -SCR reaction on the CuSO 4 /TiO 2 catalysts followed an Eley–Rideal mechanism. The reaction of gaseous NO with NH 3 adsorbed on Lewis acid sites to form N 2 and H 2 O could be the main reaction pathway, and oxygen adsorption might favor this process.
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 HAZARDOUS MATERIALS
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2018
·
IF 6.434
Guangjun Zhai,Jinguo Wang,Zimei Chen,Shuaifeng Yang,Yong Men
Three-dimensionally ordered macroporous (3DOM) Co 3 O 4 -CeO 2 catalysts with controllable Co/Ce molar ratios synthesized by colloidal crystal template method were developed to catalyze the NO x -assisted soot oxidation for the first time, and the obtained 3DOM Co 3 O 4 -CeO 2 catalysts exhibited highly enhanced soot oxidation activity. Detailed characterizations of 3DOM Co 3 O 4 -CeO 2 catalysts revealed that the highly enhanced soot oxidation activity was originated from the synergistic promoting effect by combining the macroporous effect resulted from the unique 3DOM framework, the chemical nature associated with more Co 3+ reactive sites, the surface enrichment of Ce species and the improved redox properties. Meanwhile, the high NO x storage and oxidation capacity resulted from the integrated respective merits of Co 3 O 4 and CeO 2 also accounted for the enhanced soot oxidation activity via NO x -assisted mechanism. Furthermore, the 3DOM Co 3 O 4 -CeO 2 catalysts demonstrated strong stability because of the surface enrichment of Ce species improving the thermal stability and the robust 3DOM framework inhibiting the structural collapse, showing their potential applications under practical conditions.
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
COMBUSTION AND FLAME
·
2023
·
IF 4.4
Jinglan Wang,Dandan Xu,Xuezhi Gao,Qiang Xu,Zhandong Wang,Jiuzhong Yang,Lili Xing,Junyu Tao,Beibei Yan,Guanyi Chen,Zhanjun Cheng
N-methyl pyrrole (NMP) is an important nitrogenous heterocyclic compound in bio-oils produced from biomass conversion . NMP can be used as surrogate model compound to clarify the combustion chemistry of nitrogenous fuels and NO X formation mechanism. The low- to moderate-temperature oxidation experiments of NMP are carried out in atmospheric pressure jet-stirred reactor for 0.5% NMP/oxygen/Argon mixtures at different equivalence ratios (0.5, 1.0, and 2.0) over the temperature range of 760 – 1030 K. More than twenty species, including reactants, nitrogen-containing species, and oxygenated products, are measured using synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). A detailed and comprehensive kinetic model for NMP oxidation is developed for the first time based on the pyrrole oxidation model developed by Pelucchi et al. and Chen et al.. Simulated results show that the present model can reasonably reproduce the experimental results. Rate of production analysis indicates that the H-abstraction reactions on the methyl group dominate in NMP oxidation at all equivalence ratios. NMP oxidation produces C4 and C5 nitrogen-containing compounds including pyridine and pyrrole. These species are found to be products of the primary reactions of NMP, and their formation pathways can be explained satisfactorily by the present model. The present work provides a basis to further understand the oxidation characteristics of nitrogen-containing heterocyclic fuels.
研究领域:
能源化学
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燃烧科学
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DOI
高影响因子
Catalysis Science & Technology
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2023
·Vol. 13
·期 10
·3147-3157
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IF 5
Hange Wang,Wen Chen,Wei Jin,Yueli Liu
SCR technology is considered to be the most effective method for denitrification. However, the low NOx conversion rate of the current catalysts at low temperatures limits their further application. Herein, Sn-doped modified CoAl-LDH carriers are synthesized by a hydrothermal method, and the typical hexagonal sheet structure of the MnOx(0.25)/CoSn3Al-LDO catalyst achieves 100% NO conversion at a wide range of 120–330 °C with a GHSV of 30 000 h−1, and the 100% NO conversion may be maintained at 200 °C for 30 h. After the introduction of 150 ppm SO2 at 200 °C, the NO conversion of the MnOx(0.25)/CoSn3Al-LDO catalyst is maintained at 73.4%, which is greatly improved compared with those of CoAl-LDO and MnOx(0.25)/CoAL-LDO catalysts (64.8% and 38.6%, respectively). The active components such as MnOx and Co3O4 are highly dispersed in the MnOx(0.25)/CoSn3Al-LDO catalyst. Sn doping increases the ratios of Mn4+/Mn3+ and Co3+/Co2+ as well as the adsorbed oxygen amount on the catalyst surface, and improves the redox capacity of the catalyst and increases the number of acid sites, resulting in the excellent low-temperature NH3-SCR performance of MnOx(0.25)/CoSn3Al-LDO.
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2025
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IF 11.3
Lupeng Han,Xiyang Wang,Fuli Wang,Yongjie Shen,Hengxiang Zhang,Weiwei Hu,Min Gao,Yimin A. Wu,Ming Xie,Jianfu Chen,Dengsong Zhang
Nowadays, it is challenging to achieve SO2-tolerant environmental catalysis for NOx reduction because of the thermodynamically favorable transformation of reactive sites to inactive sulfate species in the presence of SO2. Herein, we achieve enhanced low-temperature SO2-tolerant NOx reduction by manipulating the dynamic coordination environment of active sites. Engineered by coordination chemistry, SiO2-CeO2 composite oxides with a short-range ordered Ce–O–Si structure were elaborately constructed on a TiO2 support. A dynamic coordination environment of active sites is demonstrated from a Ce–O–Si local structure to a low-coordinated Ce-SO42– species in the presence of SO2. The low-coordinated Ce-SO42– species as new active sites maintain a high NO removal efficiency by preserving the good adsorption and activation capacity of NO and NH3 reactants. This work proposes a new notion to improve the SO2 resistance of catalysts by regulating the coordination environment of sulfated active sites, which is of significance for SO2-tolerant environmental catalysis in practical applications.
研究领域:
环境催化
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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
Inorganic Chemistry Frontiers
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2026
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IF 6.2
siqing Wang,Yan Zhang,Pengda Xiang,Dawei Chen,Qiling Li,Zhiyan Guo,chen chen
Electrocatalytic urea synthesis from CO2 and NOx offers a sustainable route for chemical production and environmental remediation. While grain-boundary engineering has emerged as a promising strategy to accelerate the sluggish kinetics of C–N coupling, whether it can simultaneously regulate the reaction pathways of both carbon and nitrogencontaining molecules remains unclear. Hence, we employed single-active-site TiO2 as a model catalyst and constructed polycrystalline grain boundaries to boost both the activity and selectivity of urea synthesis. Atomic-scale structural inducers (Fe) served as nucleation nodes for grain-boundary formation and promote the generation of abundant oxygen vacancies, which captured and locally concentrated electrons to facilitate the adsorption, activation, and C−N coupling of key reaction intermediates. Operando electrochemical impedance spectroscopy demonstrated enhanced interfacial charge transfer and faster interfacial response frequencies. In situ infrared spectroscopy directly tracked the adsorption and activation of both reactants as well as the formation of the critical C–N bond. This work provides a general design principle for developing advanced electrocatalysts for efficient C–N coupling.
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DOI
高影响因子
JOURNAL OF RARE EARTHS
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2021
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IF 3.712
Yiqing Zeng,Shule Zhang
Revealing the active species of the catalyst is conducive to the design of more efficient catalyst. Herein, we tried to demonstrate the roles of amorphous and crystalline structures on CePO 4 catalyst during selective catalytic reduction (SCR) of NO x by NH 3 . Higher calcination temperature promotes the transfer of amorphous structure to crystalline structure on the surface of CePO 4 . Both amorphous and crystalline CePO 4 species on CePO- X samples can provide acid sites for NH 3 adsorption, but the former can provide more acid sites. The superior redox property of surface amorphous CePO 4 species contributes to its high NH 3 -SCR activity at low temperature, but it also leads to the decrease of high temperature (>350 °C) NH 3 -SCR activity due to the oxidation of NH 3 . In contrast, crystalline CePO 4 species shows high activity only at high temperature because of its poor redox property. Therefore, it can be inferred that amorphous and crystalline structures on CePO 4 catalyst can be the efficient active species of NH 3 -SCR at low and high temperature, respectively.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
HYPERTENSION RESEARCH
·
2022
·Vol. 46
·期 4
·972-983
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IF 5.528
Shen Yuchen,Wang Zhenfeng,Su Lixin,Zheng Lianzhou,Han Yifeng,Jiao Xiaohui,Fan Xindong,Wang Deming
This study aimed to examine whether the administration of losartan can prevent acute elevation of pulmonary arterial pressure (AEPAP) induced by endovascular ethanol injection and to assess its related mechanisms. Male swine were selected and performed with absolute ethanol endovascular injection. Saline was used as the negative control. Losartan was administered preoperatively. Pulmonary arterial pressure (PAP), femoral arterial pressure (FAP) and heart rate (HR) were monitored during operations. Venous plasma and pulmonary artery (PA) tissue were harvested for analyses. Protein level was detected by Western blotting and ELISA, whereas qRT-PCR was used in mRNA detection. H & E staining and immunohistochemistry were conducted to evaluate histopathology. Ethanol injection elevated PAP in swine. The concentration of RAS ligands was elevated in plasma (all P < 0.0001) but not in PA. The level of oxidative stress increased in both plasma and PA. MRNA level of AT1R ( P < 0.01, 95% CI: 0.251–1.006), not AT2R increased in PA. Losartan failed to inhibit AEPAP after all sessions of ethanol injection, and partially reversed the ethanol-induced PA remodeling. The P38 MAPK was activated after ethanol injection and could be inhibited by losartan ( P < 0.01, 95% CI: −0.391 to −0.164). Ethanol also promoted the translocation of the P40-PHOX/P47-PHOX/P67-PHOX complex and the activation of NOX, which was independent from RAS. Endovascular ethanol injection can induce AEPAP mainly by activating RAS and P38 MAPK signaling. Losartan can partially prevent AEPAP and vascular remodeling owing to the promotion of NOX activity by ethanol.
Mechanism diagram of endovascular ethanol injection-induced acute elevation of pulmonary arterial pressure (AEPAP) partially prevented by losartan. RAS: Renin–angiotensin system; AGT: angiotensinogen; Ang I: angiotensin I; ACE: angiotensin I converting enzyme; Ang II: angiotensin II. AT1R: angiotensin II type 1 receptor. NOX2: NADPH oxidase 2. PA: pulmonary artery.
研究领域:
药理学
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心血管研究
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动物模型
✓ 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）