FUEL
·
2018
·
IF 4.908
Hao Zhou,MengYao Ge,Shiguo Wu,Bichao Ye,Yaxin Su
The selective catalytic reduction of NO with propane has been investigated with iron based monolithic catalysts supported on alumina, silica, and titania. The catalysts were characterized by N 2 -physisorption, XRD, SEM, XPS, H 2 -TPR, Py-FTIR and in situ DRIFTS technologies. The different supports had a significant influence on specific surface area, surface morphology, lattice oxygen, redox properties and the acid sites, which resulted in differences in the catalytic activity of NO reduction. The C 3 H 8 -SCR performance decreased in the order as Fe/Al 2 O 3 /CM > Fe/SiO 2 /CM > Fe/TiO 2 /CM. Fe/Al 2 O 3 /CM showed the highest activity with a nitrogen oxide conversion of 100% in the presence of oxygen at 500 °C,which is mainly attributed to the good redox properties and the abundant Lewis acid sites. Based on in situ DRIFT studies, the increase of Lewis acid sites will enhance the formation of NO 2 /NO 3 − species and acetate/formate species, then promote the catalytic activity.
研究领域:
催化化学
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环境科学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 37
·24947-24954
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IF 10.7
Xuebin Wang,Miao He,Ping Wang,Jiasai Yao,Jing Xiong,Xin Zhang,Xiaohua Sun,Yuechang Wei,Zhenxing Li
Alkali metals can control the redox potential of a reaction system as well as modify the surface electronic structure and improve the stability of a catalyst. Herein, we doped an alkali metal into a cerium manganese-based three-dimensional ordered macroporous (3DOM) catalyst for NO oxidation and soot combustion; the doping was achieved using a self-sacrificing polymethyl methacrylate template and an excess impregnation method. The introduction of alkali metals can provide a rough pore surface, which increases the contact area between the catalyst and the reactant gas. Meanwhile, alkali metal doping can promote the formation of more oxygen vacancies and unsaturated structures and increase the catalytic activity for NO oxidation and soot combustion. 5% K-doped CM-5K achieved an NO conversion rate of 81.9% at 250 °C and of nearly 100% at 320 °C. CM-5K also demonstrated remarkable stability in cycling stability tests for NO oxidation and soot combustion. This work provides a promising catalyst candidate for NO oxidation and soot combustion in practical application.
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
Frontiers in Chemistry
·
2024
·
IF 3.8
An Sufeng,Wang Peng,Wang Kuanling,Wang Xuehai,Li Baozhong,Guo Xinwen
The M/SSZ-39 catalysts (M = In, Co, Cu, Fe) with different metal species and metal loadings were synthesized using the wet impregnation method on a small-pore SSZ-39 molecular sieve. X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption-dehydrogenation and hydrogen temperature program reduction (H2-TPR) were employed to characterize the effects of various metal components and metal loadings on the performance of CH4 selective catalytic reduction of NO reaction (CH4-SCR). The characterization results showed that the In/SSZ-39 catalyst exhibited significantly higher catalytic activity compared to the Cu-, Co-, and Fe/SSZ-39 catalysts, suggesting that indium (In) is a more suitable active ingredient for the CH4-SCR reaction. The xIn/SSZ-39 (x = 1, 2, 3, x represents the In loadings of 1.0 wt%, 2.0 wt% and 3.0 wt%) catalysts, with different In loadings, all present excellent CH4-SCR performance. By varying the In loadings, the type of In species present in the catalyst can be regulated, thus enhancing DeNOx activity and CH4 selectivity in the CH4-SCR reaction. At a low temperature of 400 °C and a low CH4/NO feed ratio (CH4/NO = 1), the 3In/SSZ-39 catalyst, featuring highly active InOx clusters, achieves the best low-temperature CH4-SCR performance, with a high NO conversion rate of up to 90% and a CH4 selectivity of up to 74.2%.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Xin Xu,Bolin Xia,Amirreza Gholivand,Xiaoyu Zhang,Yunpeng Zhang,Linhui Liu,Daiqi Ye,Peirong Chen
Selective dissolution is highly promising for tailoring the structures and functions of metal oxides toward various applications. Here, we demonstrate a successful fabrication of porous γ-MnO 2 by selectively dissolving Ca in a CaMnO 3 perovskite (CMO) via dilute HNO 3 treatment. The perovskite-derived γ-MnO 2 (denoted as CMO-72 h) outperformed drastically the pristine CaMnO 3 and a commercial γ-MnO 2 in the catalytic oxidation of NH 3 and NO, two representative gaseous pollutants in the atmosphere. Physicochemical characterization by X-ray photoelectron spectroscopy and temperature-programmed techniques (including H 2 -TPR, O 2 -TPD and NH 3 -TPD) suggests that the excellent catalytic performance of CMO-72 h is associated with its low–temperature reducibility and abundant surface–active oxygen species. Specifically, acid treatment led to the oxidation of Mn 3+ to Mn 4+ on the surface, increasing significantly the Mn 4+ /Mn 3+ ratio from 0.76 (for CMO) to 1.45 (for CMO-72 h) and, meanwhile, generating additional surface oxygen vacancies . As a result, O 2 molecules can be easily adsorbed and activated on the CMO-72 h, leading to improved performance in NH 3 and NO oxidation. This study may offer new opportunities in the synthesis of high-performance Mn oxide catalysts for environmental applications.
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
CATALYSIS LETTERS
·
2025
·Vol. 155
·期 6
·1-17
·
IF 2.4
Sun Ran,Hou Kunge,Jin Xingpeng,Yang Lihui,Song Lijie,Ouyang Chuang,Hou Jianyuan,Yuan Yuan,Liu Xingang,Zhang Renxi
The development of new technologies for removal of NO and chlorobenzene in complex flue gas situations at low temperature is a complex and demanding task. Here, the synergistic removal of NO and chlorobenzene was achieved through catalysis assisted dielectric barrier discharge (DBD) mechanism under different conditions. The experimental results suggested that the increase of specific energy density (SED) and the loading of CeO 2 strengthened the treatment of NO and chlorobenzene. A higher degradation efficiency of NO and a lower production rate of NO 2 were achieved after the introduction of chlorobenzene. The removal of chlorobenzene could also be benefited from this process, and the introduction of NO promoted CO 2 selectivity of chlorobenzene. The XPS and H 2 -TPR analyses confirmed that the reaction between chlorobenzene and NO occurred by the assistance of Ce 3+ /Ce 4+ redox cycle as well as the consumption and regeneration of chemically adsorbed oxygen. During the reaction, the oxygen vacancies (OVs) caused by plasma etching promote the redox cycle and alleviate the catalyst poisoning caused by chloride ions (Cl − ). Furthermore, a comprehensive analysis of the resulting byproducts revealed phenol as the most significant intermediate in chlorobenzene degradation, while acetaldehyde emerged as the major product resulting from ring-opening processes of chlorobenzene. Utilizing chlorobenzene from flue gas subtly, this method presents a more sustainable alternative for NO reduction, showing promise for addressing industrial emission challenges. Graphical
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
RSC Advances
·
2016
·Vol. 6
·期 74
·69855-69860
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IF 3.289
Baohuai Zhao,Rui Ran,Li Sun,Xingguo Guo,Xiaodong Wu,Duan Weng
The perovskite oxides LaMnO3+δ were prepared by a citrate method and then etched by acid solution with different times. After etching, the perovskite structures of all the catalysts remained, the surface area enlarged apparently, and the NO catalytic oxidation activities were obviously promoted by increasing the etching time. Long-term experiments revealed the acceptable stability of the etched catalysts. The favorable activities of the etched LaMnO3+δ catalysts were mainly due to their high specific surface area, abundant activated oxygen species and vacancies, as well as the higher valence state of Mn ions resulting from the loss of La3+ in the perovskite structure.
研究领域:
材料科学
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环境催化
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2023
·
IF 4.6
Jing Li,Suxia Ma,Ke Ren,Nuo Xu
SSZ-13 zeolite was synthesized from fly ash using a combined alkali fusion hydrothermal method. The optimal synthesis parameters are as follows: NaOH/FA=1.4, SiO 2 /Al 2 O 3 =50, H 2 O/SiO 2 =1800, TMAda-OH/Al 2 O 3 =7, the amount of SSZ-13-seed=10%, and crystallization time and temperature were 160 °C and 40 h. Based on this, a series of fly ash-based Fe-SSZ-13 catalysts were prepared using three different methods and tested in catalytic oxidation with H 2 O 2 for NO removal. The experiment results showed that the NO removal efficiency catalyzed by Fe-SSZ-13-SSIE, Fe-SSZ-13-LIE and Fe-SSZ-13-IM were 78%, 87% and 84%, respectively. ESR was used to detect hydroxyl radicals, UV-vis, XPS and H 2 -TPR were applied to test the composition, state and distribution of iron species, while NH 3 -TPD and Py-FTIR were performed to analyze the intensity and type of acidic sites, and finally to determine the relationship between catalyst structure, active species and catalytic performance in combination with NO removal experiments. The catalytic oxidation mechanism analysis revealed that the excellent catalytic performance can be attributed to the dual function of strong Brønsted acidity on the surface and isolated Fe 3+ with high dispersion, which can rapidly decompose H 2 O 2 into ·OH and efficiently achieve NO oxidation. In conclusion, the preparation of fly ash catalysts has great potential for achieving the dual function of waste utilization and pollutant removal.
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
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2023
·
IF 5.8
Shu Wu,Jinjing Shi,Xia Chen,Lu Bai,Qiuhua Wu,Guolin Zhang
Novel multi-responsive drug delivery vehicles (CDs/ [email protected] ) were prepared by grafting amino-terminated poly (N-vinyl caprolactam) (PNVCL-NH 2 ) and amino-rich carbon dots (CDs) on the surface of aldehyde-functionalized HMSNs (HMSNs-CHO) via Schiff base reaction. The CDs were prepared from L -arginine and their surfaces were rich in guanidine . Doxorubicin (DOX) was loaded into the nanoparticles to form drug loaded vehicles (CDs/ [email protected] ) and the drug loading efficiency was 58.38%. The drug release behaviors of CDs/ [email protected] showed temperature and pH responsiveness due to the poly (N-vinyl caprolactam) (PNVCL) and Schiff base bond. The high concentration of NO released in high concentration H 2 O 2 of tumor site could induce tumor cells apoptosis. The multi-responsive CDs/ [email protected] are intriguing drug carriers, which combine drug delivery and NO release in one.
研究领域:
纳米技术
·
药学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Yuefa Jia,Shiping Li,Jianzhi Gao,Gangqiang Zhu,Fuchun Zhang,Xianjin Shi,Yu Huang,Chunli Liu
NO removal is one of the most important issues in dealing with air pollution. In this report, Z-scheme (BiO) 2 CO 3 -BiO 2-x -graphene (BOC-BiO 2-x -GR) composite photocatalyst was designed for NO removal under simulated solar light irradiation. Characterizations of physical properties of the ternary composites revealed extended light absorption and high efficient electron-hole separation. Through the optimization of the BiO 2-x content, we observed that the BOC-BiO 2-x (35wt%)-GR composite exhibited superior photocatalytic activities in NO removal as compared to pure BOC, BiO 2-x , and BOC-BiO 2-x binary composites. Detailed microstructural observation showed that the BOC-BiO 2-x heterojunction was formed between BOC (013) and BiO 2-x (111) planes. The density of state (DOS) calculation revealed that due to the different hybridization conditions in the energy bands of BOC and BiO 2-x , the Z-scheme charge transfer should be dominant at the heterojunction interface. The density functional theory (DFT) computation on the Fermi level results confirmed that energy band structure between BOC and BiO 2-x is more in favor of the transfer of photo-generated electrons from CB of BOC to the VB of BiO 2-x , which can be further enhanced by highly conductive GR sheets. The electron spin resonance (ESR) experiments results show that O 2 − and HO were produced during the photocatalytic process, which further provided evidences that the BOC-BiO 2-x (35wt%)-GR composite works as a Z-scheme photocatalyst. This work indicates that Bi-based nanomaterials can be employed as a stable and high efficient solar light active photocatalyst for NO removal in air pollution control.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Liu Yang,Jing Li,Guoqiang Cao,Yiyan Yang,Wen Luo,Zhiqi Zhang,Lizhi Feng,Xinglai Zhang,Baodan Liu
This study reports on the development of highly-efficient Pt/CuO-Fe 2 O 3 /TiO 2 monolithic catalysts for the low-temperature conversion of NO to N 2 via CO-SCR. In this case, ultrathin TiO 2 nanosheet arrays are designed to in situ grow on flexible Ti mesh to provide more spaces/areas for the loading of highly-dispersed Fe 2 O 3 and CuO active components. Furthermore, Pt nanoparticles with an average size of 1.30 nm are effectively decorated on the surface of CuO-Fe 2 O 3 /TiO 2 . The H 2 -TPR and NO-TPD results demonstrate that the excellent synergistic effect between TiO 2 , CuO, Fe 2 O 3 and trace amounts of Pt is conducive to enhance the adsorption of NO and finally promote the CO-SCR. The obtained Pt/CuO-Fe 2 O 3 /TiO 2 catalysts exhibit excellent CO-SCR performance with 100 % NO conversion, and 100 % N 2 selectivity at 250 °C, showing great potential of de-NO x application by using toxic CO as reductant in industry.
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
JOURNAL OF CATALYSIS
·
2023
·
IF 7.3
Darong He,Xinmei Ding,Shanshan Li,Yaxin Liu,Ming Zhao,Jianli Wang,Yaoqiang Chen
Deep catalytic removal of nitrogen oxides is one of the widespread research topics, mainly limited by the low temperature activity and hydrothermal stability of the first step for NO oxidation. Oxygen vacancies (O v ) and oxygen migration capacity play a crucial role in this challenge. Particularly, tuning the Mn-O coordination environment according to the radius and valence differences of dopant ions can increase O v , while accelerate oxygen migration by constructing Pt/mullite interfaces. Here, based on the hydrothermal stability of Pt/mullite to NO oxidation, we designed Mg 2+ - and Ba 2+ -doped catalysts. And the NO oxidation performance of the Mg 2+ -doped catalyst was significantly enhanced compared to the undoped catalysts (After hydrothermal aging, turnover frequency = 1.9 s −1 at 150 °C and activation energy = 21 kJ/mol). Meanwhile, all catalysts tested with simulated diesel exhaust and the NO oxidation performance showed essentially no decrease after 16 h of hydrothermal aging at 800 °C. Furthermore, X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) demonstrated the O v content of doped catalysts increased significantly. In addition, O 2 temperature programmed desorption (O 2 -TPD) and Thermogravimetry (TG) proved that the oxygen migration capacity of doped catalysts was enhanced by several times. Notably, the simple doping method is general for the modification of other mullites and worthy of industrial application.
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
·
2022
·
IF 4.654
Jing Li,Suxia Ma,Rongji Cui,Nuo Xu,Ting Pei
Solid waste fly ash can encroach on land, contaminate the environment, and jeopardize human health. An alkali fusion method combined with a hydrothermal method was adopted to prepare fly ash-derived ZSM-5 molecular sieves, and a series of Fe/ZSM-5 catalysts were also prepared to test their catalytic performance in NO oxidation with H2O2. Moreover, the characteristics of catalysts synthesized by fly ash, as well as the relationship between the structure and the catalytic activity, were analyzed in detail through multiple characterization approaches. The results gave important insights into the active sites of catalytic oxidation. They concluded that 10% Fe/ZSM-5 had the best catalytic activity in which Fe sites and Brønsted acid sites collectively provided the catalytic functionality, and 92% NO removal efficiency was obtained achieved under optimal experimental conditions. This work provided a new way for recycling fly ash and developing low-cost catalysts for NO removal.
研究领域:
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）