APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
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IF 24.319
Shaomian Liu,Wenjuan Xue,Yongjun Ji,Wenqing Xu,Wenxing Chen,Lihua Jia,Tingyu Zhu,Ziyi Zhong,Guangwen Xu,Donghai Mei,Fabing Su
Simultaneously improving both NO x conversion and N 2 selectivity in the selective catalytic reduction of NO by CO (CO-SCR) under O 2 -containing conditions is highly challenging because of the competitive reactions of NO x and CO with O 2 . Here, we demonstrate that the interfacial oxygen vacancies (IOVs) generated at the Co 3 O 4 -CeO 2 heterointerfaces by ball-milling-induced strain can remarkably boost both NO x conversion and N 2 selectivity in the temperature range of 100–400 °C. The Co 3 O 4 -CeO 2 -IOV catalyst achieved approximately 100% NO x conversion and 100% N 2 selectivity (200–350 °C, 1–5 vol% O 2 , and 20,000 h −1 ); even under 10 vol% O 2 , it still showed good catalytic performance. The spectroscopy analysis and theoretical calculations reveal that compared with O 2 activation, IOVs are more favorable for the rate-limiting step of NO adsorption and dissociation. This work provides an effective strategy to create IOVs within metal oxide composite catalysts using ball-milling-induced interfacial strain for improving CO-SCR performance.
研究领域:
材料科学
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环境催化
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Huimin Chen,Xin Li,Wenjiang Li,Aoao Lu,Chenguang Li,Qiang Li,Dabin Liu,Hongfei Ma,Binbin Wang
The safe long-term storage of nitrocellulose (NC) has become increasingly challenging under extreme environmental conditions due to accelerated NO x release, which promotes self-catalytic decomposition of NC. In this study, Tröger’s base (TB) was integrated into porous organic polymers (POPs) to achieve dual functionality: efficient physical adsorption and stable in-situ chemical fixation of NO x within confined pore spaces. Solid-state CP/MAS 13 C NMR spectroscopy and quantum chemical calculations were employed to confirm that NO x immobilization occurs preferentially at the ortho positions of tertiary amine moieties on aromatic rings. Among the synthesized materials, the polymer resulting from the Trögerization of the Tetrakis (4-aminophenyl) methane (TAPM-TB) was identified as the optimal adsorbent, characterized by accessible ortho-active sites, a microporous structure, and an exceptional NO x uptake capacity of 3.31 mmol/g under standard conditions. Furthermore, TAPM-TB was demonstrated to extend the stability time of NC by 3.23 times in methyl violet tests. These findings highlight a novel strategy for designing materials capable of simultaneous physical adsorption and stable chemical immobilization of NO x or other gases.
研究领域:
材料科学
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环境化学
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高分子化学
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物理化学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
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IF 0
You Mengyun,Wu Shufeng,Feng Xiaotong,Zhao Yong,Wang Yubin,Zhang Zhang
The enhancement effect of Ce modification on V 2 O 5 -WO 3 /TiO 2 catalysts at low temperatures was investigated for the selective catalytic reduction (SCR) of NO x with NH 3 (NH 3 -SCR). By adding 9% CeO 2 to 0.5%V 2 O 5 -3%WO 3 /TiO 2 catalyst, the low-temperature denitrification performance of Ce 9 V 0.5 W 3 Ti catalyst after Ce modification was significantly improved, achieving a NO conversion above 90% within a broad temperature range of 200–350℃, with catalytic activity comparable to that of 3% V 2 O 5 -3% WO 3 /TiO 2 . The catalysts were characterized by XPS, H 2 -TPR, NH 3 , and NO-TPD. The results indicated that the Ce additive could enhance the adsorption of NO x on Ce 9 V 0.5 W 3 Ti catalyst due to the synergetic interaction among the Ce and V, W species. The interaction between V and Ce also promoted the formation of V 5+ and Ce 3+ on the surface of the catalyst, which was conducive to enhancing the adsorption and oxidation capacity of the catalyst for NO. Additionally, the introduction of Ce led to a substantial deposition of nitrate species on the surface of the catalyst, especially the increase of nitrite species, which was beneficial to the NH 3 -SCR reaction process, resulting in a significant enhancement of the catalyst’s low-temperature catalytic activity.
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
PubMed
ENERGY & FUELS
·
2025
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IF 5.3
Fang Wang,Xueyan Wu,Yuxuan Han,Yan Lv,Jixi Guo,Xiaoman Li,Yaping Zhang
In cement kiln flue gas emissions, high concentrations of alkali and alkaline earth metals cause the deactivation of the NbCe/Ti catalysts, significantly reducing their operational lifespan under industrial conditions. Here, the NbCe-loaded titanium nanotubes (NbCe/TiNTs) catalyst has been synthesized via hydrothermal and impregnation methods. The NbCe/TiNTs catalyst exhibits superior resistance to potassium (K) and calcium (Ca) poisoning. Notably, NbCe/TiNTs catalyst maintains high NOx conversion across a wide temperature range (192–350 °C). The 5Ca-NbCe/TiNTs and 3K-NbCe/TiNTs catalysts achieve a 90% NOx conversion at 235 and 242 °C, respectively, demonstrating remarkable resistance to K and Ca poisoning. The results indicate that TiNTs supports enhance both the specific surface area and surface acid sites of the catalyst, synergistically improving its resistance to K and Ca poisoning. Furthermore, an in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) study elucidates selective catalytic reduction with the NH3 (NH3-SCR) reaction mechanism, revealing dual contributions from both the Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) mechanisms on the catalyst. This work provides a research direction for enhancing the alkali poisoning resistance of NOx removal catalysts.
研究领域:
环境催化
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材料科学
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化学工程
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表面科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2021
·Vol. 8
·期 4
·045509
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IF 1.62
Ruian Wu,Jiang Jin,Kun Li,Lei Zhao,Hua Zhang
The FeaTibOx catalyst was loaded into the pores of porous ceramic using impregnation method for removing nitrogen oxides with selective catalytic reduction (SCR) technology. The catalytic performance over FeaTibOx catalyst was studied in detail. The Fe6Ti1Ox catalyst displayed more than 95% NOx conversion within the range of 280 °C–400 °C, and still maintained 97% NOx conversion when 300 ppm SO2 and 10 vol.% water vapor were introduced at the testing temperature of 300 °C. The influence factors (including filtration velocity, NH3/NO mole ratio and oxygen concentration) for NOx conversion over Fe6Ti1Ox catalyst were also studied. The suitable NH3/NO mole ratio and oxygen concentration was 0.9 and 6%, respectively. The XRD, N2-BET, H2-TPR, NH3-TPD and XPS were employed to investigate physicochemical property of the FeaTibOx catalyst. The results illustrated that Fe6Ti1Ox catalyst has hematite Fe2O3 and TiO2 structure, better redox properties and stronger surface acid.
研究领域:
环境科学
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催化材料
✓ 已验证
DOI
高影响因子
Thermal Science and Engineering Progress
·
2023
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IF 4.8
Shuai Guo,Guoliang Qi,Jialiang Gao,Deng Zhao,Kaixin Chen,Chenchen Zhao,Xingcan Li,Guangyu Li
Pyrolysis is an effective method for safely disposing of sewage sludge via conversion into a usable energy source. However, municipal sludge has a high protein content, which is a major source of NO x precursors. This study investigated the effect of CaO on NO x precursor formation during glutamate pyrolysis and demonstrated that CaO occupies the carbo x yl site of glutamic acid at 320 °C, which delays its decomposition and promotes the conversion of glutamic acid from a five- to a si x -membered ring. At 400 °C, heterocyclic nitrogen in the tar peaked from 4.87 to 53.87% after adding CaO. As the temperature increases to 480 °C, CaO might promote the conversion of heterocyclic nitrogen into tricyclic piperazine dione in the tar, which subsequently decomposed to produce HCN in large quantities. At 480 °C, CaO contributed to the decrease in pyrrole, pyridine, and quaternary nitrogen in the semi-coke from 24.81%, 12.93%, and 7.43% to 1.91%, 5.97%, and 1.43%, respectively and promoted HCN hydrolysis to form NH 3 . At 480–680 °C, CaO interacted with NH 3 to form CaCN 2 . The product of CaC x N y decomposition—CaC x —captured NH 3 . At high temperatures, CaO inhibited HCN release, which might be related to the reaction between CaO and HCN to form CaC x N y , subsequently reconverted into CaO at temperatures above 680 °C. These findings provide novel insights into the influence of CaO on amino acid pyrolysis to produce NO x precursors and the regulation of NO x precursor production.
研究领域:
环境科学
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能源与燃料
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Xiaolei Hu,Weiye Qu,Junxiao Chen,Dongrun Xu,Jing Liu,Yangyang Dong,Rui Liu,Zhen Ma,Xingfu Tang
Selective catalytic reduction (SCR) of NO x with NH 3 over V 2 O 5 -based catalysts has been widely used to control NO x emissions from power plants, but its application is largely limited in other industrial boilers because of insufficient catalytic efficiency at low temperatures. Here we resolve this problem by mechanistically designing a highly active Ce-W/TiO 2 catalyst with reactants-coupling dual catalytic sites. The results demonstrate that W and Ce are highly dispersed on the surfaces of Ce-W/TiO 2 to form dual catalytic sites, which act as acid-base pairs favorable for NH 3 and NO adsorption, respectively, thereby allowing the reaction of adsorbed NH 3 on the W site with oxidized NO species (NO 3 − ) adsorbed on the adjacent Ce site to proceed along a low-activation-energy pathway via Langmuir-Hinshelwood mechanism. Compared with Ce/TiO 2 , a W-Ce synergy gives rise to more abundant Ce 3+ on Ce-W/TiO 2 , which facilitates the activation of O 2 during SCR process, thus improving the low-temperature SCR performance. Therefore, the design of the dual catalytic sites based on the properties of reactants provides an alternative approach to developing highly active SCR catalysts.
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
Engineering
·
2025
·
IF 11.6
Ying Zhu,Jingjing Liu,Guangzhi He,Shaohua Xie,Wenpo Shan,Zhihua Lian,Fudong Liu,Hong He
Catalytic activity and hydrothermal stability are both crucial for the application of the selective catalytic reduction of NO x with NH 3 (NH 3 -SCR catalyst) in diesel vehicles. In this study, a tin (Sn)-modified Ce–Nb mixed-oxide catalyst was synthesized as an NH 3 -SCR catalyst for NO x emission control. After the introduction of Sn, both the NH 3 -SCR activity and the hydrothermal stability of the catalyst were remarkably promoted. Even after hydrothermal aging at 1000 °C, the developed Ce 1 Sn 2 Nb 1 O x catalyst achieved more than 90% NO x conversion at 325–500 °C. Various methods, including N 2 -physisorption, X-ray diffraction, in-situ high-temperature X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray absorption fine-structure spectroscopy, temperature-programmed reduction of hydrogen, temperature-programmed desorption of ammonia, and density functional theory calculations were used to investigate the promotional effects induced by the Sn species. The characterization results showed that the addition of Sn not only promoted the formation of the Ce–Nb active phase but also improved its thermal stability, contributing to the excellent NH 3 -SCR performance and hydrothermal stability. This study provides an excellent sintering-resistance catalyst for the application of diesel engine NO x emission control.
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
CHINESE JOURNAL OF CATALYSIS
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2020
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IF 6.146
Xiaona Liu,Yi Cao,Nana Yan,Chao Ma,Lei Cao,Peng Guo,Peng Tian,Zhongmin Liu
The high-temperature (HT) and low-temperature (LT) hydrothermal stabilities of molecular-sieve-based catalysts are important for the selective catalytic reduction of NO x with ammonia (NH 3 -SCR). In this paper, we report a catalyst, Cu 2+ loading SAPO-17, synthesized using cyclohexylamine (CHA), which is commercially available and inexpensive and is utilized in NH 3 -SCR reduction for the first time. After systematic investigations on the optimization of Si and Cu 2+ contents, it was concluded that Cu-SAPO-17-8.0%-0.22 displays favorable catalytic performance, even after being heated at 353 K for 24 h and at 973 K for 16 h. Moreover, the locations of CHAs, host–guest interaction and the Brönsted acid sites were explored by Rietveld refinement against powder X-ray diffraction data of as-made SAPO-17-8.0%. The refinement results showed that two CHAs exist within one eri cage and that the protonated CHA forms a hydrogen bond with O4, which indicates that the proton bonding with O4 will form the Brönsted acid site after the calcination .
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
Nature Communications
·
2026
·
IF 18.1
Li Guobo,Ji Jian,Liao Meiyuan,Wang Penglu,Hu Xiaonan,Chen Lei,Hou Xueyan,Tang Changjin,Liu Wenming,Peng Honggen
Developing highly efficient, stable, and wide-temperature NH 3 -SCR catalysts is one of the major challenges in industrial NO x emission control. Herein, we present an oxide-zeolite (OXZEO) hybrid design strategy for overcoming the challenge by spatially separating the NH 3 storage and redox functions via isolated zeolitic Brønsted (B) acid sites, in contrast to conventional regulation strategies that rely on Lewis acid sites. Through a combination of in situ spectroscopy, in situ mass spectrometry, ab initio molecular dynamics, and density functional theory, we identify a previously unrecognized denitrification (deNO x ) mechanism unique to the OXZEO system. Zeolitic B acid sites act as highly regulated NH 3 storage, and the stored NH 3 desorbs and migrates to oxide active sites as NH 3 and NH 4 + , the latter effectively suppressing high-temperature NH 3 over-oxidation. Using CeSnO x /Beta as the main model system for mechanistic investigation, we further demonstrate that this strategy can be generally extended to diverse zeolite topologies (BEA, CHA, MFI, FAU) and Ce-/Mn-based oxides, affording catalysts that achieve >80% NO x conversion and ~100% N 2 selectivity over a temperature window exceeding 300 °C. This work highlights zeolite-mediated NH 3 storage in deNO x , providing mechanistic insight into OXZEO structure-property relationships and guiding the development of next-generation NH 3 -SCR catalysts.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic and Nano-Metal Chemistry
·
2021
·
IF 1.716
Changsheng Qu,Hao Zhou,Dongyao Xu,Jiaojiao Guo,Danyang Zhao,Xuewei Guo,Luyuan Xing
In this study, the manganese was loaded on three different zirconia crystal types by ultrasonic impregnation method, and the performance of selective catalytic reduction (SCR) of NOx with NH3 was tested. The characteristics of the catalytic were tested by BET, XRD, SEM, and XPS. It was founded that the performances of unloaded different crystal zirconia was basically the same which were less than 40%. Compared with unloaded catalyst, the DeNOx performance of catalysts after loaded manganese was greatly improved, and the crystal type had obvious influence on the DeNOx performance of Mn/x-ZrO2. The Mn/m-ZrO2 had the highest DeNOx performance (90.97% at 240 °C) compared with the Mn/t-ZrO2 and Mn/c-ZrO2. The difference of crystal type made Mn/m-ZrO2 have lower surface Mn average valence states and more oxygen vacancy, which made it have best DeNOx performance. The effects of SO2, H2O, and alkali metal on DeNOx efficiency were also tested.
研究领域:
环境科学
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催化材料科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
·
IF 9.038
Xiaoming Zhou,Zhuoyuan Chen,Zhiyong Guo,Haiping Yang,Jingai Shao,Xiong Zhang,Shihong Zhang
A series of dual metal incorporated CuCex-SAPO-34(x = 0–0.04) samples were synthesized using one-pot hydrothermal method with diethylamine as organic structure-directing agent for selective catalytic reduction of NO x by NH 3 . The catalytic properties were elucidated in detail with physicochemical properties being analyzed using various instruments. All the catalysts exhibited typical SAPO-34 crystal structures with high specific surface areas. With the dual-metal incorporation, the surface acidity and amount of isolated Cu 2+ , which may be active sites for NH 3 -SCR, were significantly enhanced. However, excessive Ce restrained the formation of isolated Cu 2+ due to its occupation of cationic sites. Therefore, the 0.05CuCe0.02-SAPO-34 exhibited high NO conversion (≥80%) at 168°C-500°C. Furthermore, the NH 3 -SCR mechanism over different catalysts was investigated in-situ DRIFTS experiments. For the 0.05Cu-SAPO-34, the adsorbed NH 3 species react with gaseous NO and following the E-R mechanism throughout the reaction temperature range. Meanwhile, adsorbed NO 2 was detected and reacted with the adsorbed NH 3 species according to the L-H mechanism in low-temperature region. In contrast, the NH 3 -SCR reaction over the 0.05CuCe0.02-SAPO-34 primarily followed the E-R mechanism throughout the temperature range. The L-H mechanism was cut off due to the loss of the adsorption ability of nitrous species at high temperatures., resulting in NO conversion decreasing.
研究领域:
环境科学
·
材料科学
✓ 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）