CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Minghao Shi,Jihui Yang,Mingjia Zhang,Shule Zhang,Qin Zhong
The Ce-based catalysts show promising activity in the selective reduction of NO x with NH 3 (NH 3 -SCR) at medium and low temperatures, yet their limited sulfur tolerance hinders broader application. We have developed a catalyst by confining CeO 2 within the mesopores of ZSM-5 zeolite (CeO 2 @ZSM-5), resulting in uniform dispersion and ultra-small CeO 2 nanoparticles (<10 nm). This distinctive structure enhances the interaction between the carrier and active species, reducing the catalyst's surface basicity and its affinity for acidic SO 2 gas. Additionally, the small CeO 2 particle size leads to an increased Ce 3+ concentration, which inhibits the reaction between Ce active sites and SO 2 . Employing a dual strategy of reducing adsorption and inhibiting reactions, we significantly minimized the impact of SO 2 on NH 3 -SCR. Impressively, common Ce-based catalysts become deactivated due to the formation of corresponding sulfates through reaction with SO 2 , however, CeO 2 @ZSM-5 achieves NO x conversion above 98% and N 2 selectivity of 100% within the temperature range of 250 °C to 450 °C. The addition of 100 ppm SO 2 does not significantly affect NH 3 -SCR activity. This study provides an effective approach to mitigate SO 2 adsorption and reactions, offering a valuable strategy for the development of highly efficient sulfur-resistant catalysts.
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JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Xiaoqiang Wang,Yue Liu,Zhongbiao Wu
Low-medium temperature NH 3 -SCR technology has been applied for years in municipal solid wastes incineration (MSWI) to control the emissions of nitrogen oxides . Unlike coal-fired flue gases , the tail gas from MSWI contains high levels of heavy metals in fly ash, especially the zinc species, which may harm SCR catalysts. As such, in this paper, the deactivation mechanism of different zinc species (ZnO, ZnSO 4 and ZnCl 2 ) on the Sb-CeZr 2 O x catalysts and the co-effects of zinc species and gas-phase pollutants (including SO 2 and HCl) were investigated. The experimental results indicated that the deactivation rate of various poisoning zinc species was in the order of ZnCl 2 > ZnSO 4 > ZnO. Moreover, the interactions between zinc and antimony species would disrupt the structure of the Sb-Ce mixed oxides to decrease the redox ability, consequently suppressing the ammonia activation and NO adsorption. Furthermore, such damaging effects on catalyst structures would promote the formation of bulk-like sulfate species in the presence of SO 2 , resulting in a decreased mobility of surface oxygen species, which significantly decrease the sulfur resistance. However, the presence of HCl did not show an evident co-effect on the Zn poisoned sample owing to the limited coverage of the chlorine deposition.
研究领域:
环境科学
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催化化学
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高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
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2025
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IF 3.9
Chenhui Hu,Kaimin Du,Zuoxi Zhuo,Chunhong Liu,Hongbing Lv,Wanjue Wang
To address the challenges of efficient and safe denitrification under actual flue gas conditions of internal combustion engine, high-temperature SCR molecular sieve catalyst were prepared and evaluated both in laboratory scale and industrial scale. A comprehensive characterization via TG, XRD, N₂ adsorption-desorption, SEM, and TEM confirmed the robust thermal stability of the molecular sieves catalyst. The molecular sieve catalyst system was commissioned in a 4275 kW distributed natural gas internal combustion engine demonstration facility and successfully passed the 72 h trial running, achieving with over 94 % NO x conversion efficiency and less than 40 mg/m 3 outlet NO x concentration at a temperature range of 440–525 °C. Compared to conventional V-based catalyst, the molecular sieve catalyst not only achieved additional reductions of 2 kg/h NO x and 38 kg/h CO 2 emissions, along with a nearly 2 % improvement in internal combustion engine efficiency, but also effectively mitigated the risk of system shutdown caused by low cylinder temperatures in exhaust gas purification systems, being considered as a promising catalyst for high-temperature applications, including gas-fired, hydrogen/ammonia-fueled, and biogas internal combustion engines.
研究领域:
环境催化
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能源工程
·
污染控制技术
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材料科学
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高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Yuxi Meng,Shaomian Liu,Yixi Wang,Wenqing Xu,Jiajian Gao,Sansan Yu,Fabing Su,Tingyu Zhu
Selective catalytic reduction of NO using CO (CO-SCR) is a promising technology for the purification of NO in the flue gas. However, the presence of O 2 significantly inhibits the activity of the CO-SCR catalyst. Herein, we synthesize a hollow Mn-doped CeO 2 @Co 3 O 4 catalyst (Mn-CeO 2 @Co 3 O 4 ), which achieved 82% NO conversion, 100% CO conversion, and 78% N 2 selectivity under 5 vol% O 2 at 200 °C, superior to those of CeO 2 @Co 3 O 4 and Co 3 O 4 @CeO 2 catalysts. The characterization results indicate that the strong electronic interaction at the heterointerfaces between Co 3 O 4 and CeO 2 plays a crucial role in promoting selective adsorption of NO. Furthermore, the Mn doping into the Co 3 O 4 lattice of the catalyst facilitates the conversion of N 2 O intermediates, thereby enhancing the overall activity. This research provides a new strategy for the design and synthesis of CO-SCR catalysts.
研究领域:
催化
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环境科学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2025
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IF 11.3
Wenjie Liao,Ling Zhou,Xiaoqiang Wang,Yue Liu,Zhongbiao Wu
Both improving the activity and reducing SO3 emissions during selective catalytic reduction of NOx by the NH3 (NH3–SCR) process over commercial V–Ti-based catalysts remain a challenge. Herein, Ce and P cooperatively modified the VMo/Ti catalyst to address this challenge. Within the temperature range of 250–350 °C, the optimal VMoCeP/Ti catalyst achieved a NO conversion of more than 95% and maintained a SO2 oxidation ratio below 1.0%. The enhanced SCR activity of the modified catalyst could be attributed to the improvement in surface acidity and redox capacity by the addition of Ce and P, which would promote NH3 adsorption and activation. Meanwhile, Ce and P coaddition could regulate the surface structure of vanadyl species from predominantly polymeric to a more dimeric form, which could also promote the SCR reaction. More importantly, except for the suppressed sulfation of vanadium species, both a lower proportion of polymeric vanadyl species and the strong interactions among V–Ce–P species could raise the energy barrier of the decomposition of sulfated vanadium species into SO3, thereby inhibiting SO2 oxidation. This work provided novel insights into developing efficient SCR catalysts with low SO2 oxidation ratios for both the academic and industrial fields.
研究领域:
催化化学
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环境化学
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材料科学
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化学工程
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DOI
PubMed
高影响因子
ENERGY & FUELS
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2023
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IF 5.3
Xiao Tan,Yiming Zhou,Suitao Qi,Guangxu Cheng,Chunhai Yi,Bolun Yang
As one of the important atmospheric pollutants, the removal of NO in flue gas at low temperatures is still a severe challenge. Selective catalytic reduction (SCR) with urea is an effective method for NO removal at low temperatures. Herein, through directly loading urea, an Fe-modified Mn-based molecular sieve catalyst with good low-temperature urea-SCR activity was prepared by a stepwise impregnation method. The results show that with a mass ratio of Mn/Fe of 10:0.5 and a calcination temperature of 500 °C, the catalyst loaded with 15 wt % urea had the highest catalytic activity of 98.5% at 250 °C. Online mass spectrometry results show that NH3 formed from the decomposition of urea reacts with NO when the temperature is above 150 °C, while urea directly reacts with NO below 150 °C. The density functional theory calculation demonstrates that the doping of Fe weakens the strength of the Mn–O bond in MnO2, which makes NO easier to combine with lattice oxygen to oxidize into NO2, thereby promoting the whole urea-SCR reaction. This work provides an overall perspective and theoretical support for the design of urea-SCR catalysts over a wide temperature range.
研究领域:
环境科学
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催化
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大气污染控制
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DOI
高影响因子
CATALYSIS LETTERS
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2025
·Vol. 156
·期 1
·21
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IF 2.4
Yang Jihui,Shi Minghao,Zheng Jiahao,Zhang Shule,Zhong Qin
Ammonia Selective Catalytic Reduction (NH₃-SCR) is highly effective for nitrogen oxide (NO x ) removal, yet its low-temperature activity remains a key limitation for broader applications. We developed an innovative series of microporous N, O-codoped carbon catalysts (NOAC-x) that facilitate the fast SCR reaction. Results demonstrate that the synergy between catalyst micropore structure and surface functional groups governs denitrification performance: Low-temperature calcination induces pore blockage by nitrogen-containing groups (pyridinic N), reducing specific surface area and weakening NH₃/NO adsorption capacity.Moderate calcinatio promotes partial decomposition of nitrogen groups, optimizing the micropore structure while preserving active sites such as carboxyl groups and pyridinic N, thereby significantly enhancing catalytic activity.High-temperature calcinatio triggers pore collapse and decomposition of active groups, degrading performance.NOAC-600 achieved 95% NO x conversion at 120 °C and exhibited merely a 2% activity decline during a 108-hour stability test. This work provides theoretical guidance for designing microporous N, O-dual-doped carbon-based catalysts and underscores the critical importance of micropore structure and surface chemistry optimization in low-temperature SCR technology. Graphical
研究领域:
环境催化
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材料化学
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大气污染控制
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碳材料科学
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表面化学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Shuhao Li,Feng Wang,Derrick Ng,Simon James,Zongli Xie,Boxiong Shen
Supported catalysts have been extensively investigated and implemented in the industry due to their cost-effectiveness and promising catalytic performance. However, due to the general inert nature of the support itself, its role in the catalyst performance is often neglected and therefore not well understood despite the consideration of the physical properties of the support. This study applies the concept of electronic metal-support interaction (EMSI) to explore the impact of various supports on the active metals in Fe-Ni-based catalysts for the CO-selective catalytic reduction reaction. Through density functional theory calculations and several advanced characterizations, it can be confirmed that the EMSI effect can modify the valence states of active metals and foster interaction between different active metals, thereby influencing the reactant adsorption and catalyst performance greatly. These findings highlight the significant impact of the support on the chemical states of active metals, having far-reaching implications for designing and optimizing the supported industrial catalysts.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
Tungsten
·
2024
·
IF 5.6
Zhang Zhi-Qi,Yang Liu,Luo Wen,An Vladimir,Li Jing,Liu Bao-Dan
The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas catalysis. In this study, we have developed a novel approach to fabricate highly efficient V 2 O 5 -WO 3 /TiO 2 monolithic mesh catalysts for NO x reduction at low temperatures. First, TiO 2 nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal method. Then, super-small traces of WO 3 and V 2 O 5 active nano-species were subsequently deposited on TiO 2 nanosheets using the deposition–precipitation method. Compared to traditional ceramic-based V 2 O 5 -WO 3 /TiO 2 catalysts, our V 2 O 5 -WO 3 /TiO 2 monolithic mesh catalyst exhibits superior mechanical performance, excellent thermal conductivity, lower pressure drop, higher utilization of active components, and stronger synergistic effects. Significantly, the V 2 O 5 -WO 3 /TiO 2 monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NO x conversion at 220 ℃, and remarkable long-term SO 2 tolerance and water resistance in the selective catalytic reduction (SCR) of NO x with NH 3 . The SCR reaction of tiny V 2 O 5 and WO 3 active species supported on TiO 2 nanosheets directly demonstrated to follow the Eley–Rideal mechanism by in situ infrared spectra.
研究领域:
催化
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环境科学
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材料科学
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高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2013
·
IF 2.145
Rui-tang Guo,Yue Zhou,Wei-guo Pan,Jie-nan Hong,Wen-long Zhen,Qiang Jin,Cheng-gang Ding,Shi-yi Guo
CeO 2 /Al 2 O 3 catalysts prepared by three methods were investigated for selective reduction of NO with NH 3 . It was found that the catalyst prepared by the single step sol–gel method had the best SCR activity and SO 2 resistance performance. From the results of BET, XRD, TPD and TPR, it can be concluded that large surface area, strong interaction, highly dispersed nano-crystalline ceria , high NH 3 adsorption capacity and good redox ability might be the main reasons for the excellent performance of CeO 2 /Al 2 O 3 catalyst prepared by the single step sol–gel method.
研究领域:
催化
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环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Xuanxuan Jia,Hao Liu,Yu Zhang,Wei Chen,Qing Tong,Guangxia Piao,Chuanzhi Sun,Lin Dong
In recent years, Fe-based catalysts for the selective catalytic reduction of NO with NH 3 (NH 3 -SCR) have been attracting more attention. In this work, a novel Fe-Sb binary metal oxide catalyst was synthesized using the ethylene glycol assisted co-precipitation method and was characterized using a series of techniques. It was found that the catalyst with a molar ratio of 7:3 (Fe:Sb) displayed the best NH 3 -SCR activity with 100% conversion of NO x (nitrogen oxides) over a wide temperature window and with good resistance to H 2 O + SO 2 at 250 °C. The X-ray photoelectron spectroscopy (XPS) and in situ diffused reflectance infrared Fourier transform spectroscopy ( in situ DRIFTS) of NO x adsorption results suggested that strong electron interactions between Fe and Sb in Fe-O-Sb species existed and electrons of Sb could be transferred to Fe through the 2Fe 3+ + Sb 3+ ↔ 2Fe 2+ + Sb 5+ redox cycle. The introduction of Sb significantly improved the adsorption behaviour of NO x species on the Fe 0.7 Sb 0.3 O x surface, which benefitted the adsorption/transformation of NO x , thereby facilitating the NH 3 -SCR reaction. In addition, the Fe 0.7 Sb 0.3 O x catalyst demonstrated a good tolerance of H 2 O and SO 2 , since the decomposition of NH 4 HSO 4 on the catalyst surface was promoted by the introduction of Sb.
研究领域:
催化
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环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF CATALYSIS
·
2026
·
IF 6
Yufeng Yang,Shijing Zhang,Jiamei Ma,Jiating Shen,Jiajun Huang,Xianglan Xu,Xiuzhong Fang,Junwei Xu,Xiang Wang
Adopting effective methods to identify clearly the active surface sites is crucial to engineer high-performance catalysts. To develop cost-effective and applicable NH 3 -SCR catalysts, the distribution states of Ag on HZSM-5 support have been identified by XRD and XPS extrapolation methods. As quantified, Ag dispersion on HZSM-5 has a threshold of 0.12 mmol Ag/100 m 2 . Above the threshold, bigger Ag 0 particles with better capability to activate O 2 and NO x molecules can be formed, thus achieving Ag/ZSM-5 catalysts with much better reaction performance below 300 °C. In contrast, below the threshold, Ag is mainly present in the form of highly dispersed nano-clusters/micro-crystallites, and partly as Ag + ions, thus being unfavorable to the reaction at low temperature. DFT calculation has testified that the aggregated Ag 0 particles with bigger sizes (>5 nm) have weaker interfacial interaction with the support, thus showing better capability to activate the reactant molecules. The optimal NH 3 -SCR performance is achieved on 8% Ag/ZSM-5 with a mean Ag size of 8.6 nm and a Ag 0 /Ag + ratio of 1.72, on which 100% NO conversion with a wide window from 250 to 400 °C can be achieved with H 2 assistance. In conclusion, both the Ag particle size and Ag 0 /Ag + ratio are the two main factors determining NH 3 -SCR performance on Ag/ZSM-5 catalysts.
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