Energies
·
2021
·Vol. 14
·期 24
·8539
·
IF 3.004
Lijian Wang,Kang Zhang,Yi Qiu,Huiyun Chen,Jie Wang,Zhihua Wang
The sulfur-iodine (SI) cycle holds great promise as an alternative large-scale process for converting water into hydrogen without CO2emissions. A major issue regarding the long-term stability and activity of the catalysts is their poor sulfur deactivation resistance in the HI feeding process. In this work, the effect of Ru addition for enhancing the activity and sulfur resistance of SiO2-supported Ni catalysts in the HI decomposition reaction has been investigated. The presence of H2SO4molecules in the HI results in severe sulfur deactivation of the Ru-free Ni/SiO2catalysts by blocking the active sites. However, Ni–Ru/SiO2catalysts show higher catalytic activity without sulfur-poisoning by 25% and exhibit more superior catalytic performance than the Ru-free catalyst. The addition of Ru to the Ni/SiO2catalyst promotes the stability and activity of the catalysts. The experimental trends in activity and sulfur tolerance are consistent with the theoretical modeling, with the catalytic activities existing in the order Ni/SiO2< Ni–Ru/SiO2. The effect of Ru on the improvement in sulfur resistance over Ni-based catalysts is attributed to electronic factors, as evidenced by theory modeling analysis and detailed characterizations.Keywords:hydrogen production;SI cycle;HI decomposition;bimetallic catalysts;sulfur-tolerant
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Chengzhi Wang,Zhenbang Tian,Weiqing Huang,Jingyuan Hu,Xing Xing
Owing to the different reaction properties and deactivation mechanisms caused by the structural discrepancy of monolithic catalysts, abundant scientific results of powder or granular NH 3 -SCR catalysts have still not sufficiently robustly applied in recent years. Furthermore, minimal research has been focused on monolithic catalysts. As a result, this work prepared monolithic Mn-Fe-Ce/Al 2 O 3 catalysts by active component impregnation (ACI-Mn-Fe-Ce/Al 2 O 3 ) and precursor impregnation methods (PI-Mn-Fe-Ce/Al 2 O 3 ) and investigates the long-term SO 2 and H 2 O resistance of the catalysts. Compared with the PI-Mn-Fe-Ce/Al 2 O 3 catalyst, the monolithic ACI-Mn-Fe-Ce/Al 2 O 3 catalyst showed better performance. The catalytic activity follows a bell-shaped curve with an optimal performance at a drug loading of 5 %. The ACI-Mn-Fe-Ce/Al 2 O 3 catalyst exhibits long-term resistance to SO 2 and H 2 O and can still convert more than 70 % NO x after 168 h of SO 2 and H 2 O resistance test. Characterization of the ACI-Mn-Fe-Ce/Al 2 O 3 catalysts before and after the reaction showed that the reducibility decreased after the reaction, and more Mn 4+ was transformed into Mn 2+ to weaken the catalytic activity. However, more Fe 2+ and Ce 3+ were generated during the reaction, increasing the number of oxygen vacancies, oxygen defects, and hydroxyl-like groups, all of which would contribute to a certain extent to counteract the passivation effect of SO 2 on the catalysts. In situ DRIFTs analysis shows that the formation of surface sulfates has a minimal effect on the adsorption of NO, but it does affect the adsorption of coordinated NH 3 on Lewis acid sites. This work elucidates the deactivation details of Mn-Fe-Ce/Al 2 O 3 catalysts from the perspective of physicochemical properties, which provides a reference for the development of better low-temperature SO 2 -resistance catalysts for industrial applications.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2020
·Vol. 7
·期 12
·125502
·
IF 1.929
Lei Zhao,Kun Li,Ruian Wu,Hua Zhang,Jiang Jin
The catalytic filter was fabricated by supporting selective catalytic reduction (SCR) catalyst on the low-density ceramic (LDC) for the removal of dust and nitrogen oxides (NOx) in the flue gases at relative low temperature. MnOx–ZrO2/TiO2 catalyst was selected as SCR catalyst. The NOx and dust removal efficiency, filter resistance, regeneration performance and anti-sulfur performance were investigated. The result showed that the NOx removal efficiency at 180°C reached 98.4% (1 m/min filtration velocity) for 6 wt% MnOx–ZrO2/TiO2 catalytic filter with Mn/Zr molar ratio of 2. Furthermore, MnOx–ZrO2/TiO2 catalytic filter performed good anti-sulfur performance. In the presence of 10 vol% water vapor and 100 ppm SO2 at 180 °C, the NOx removal efficiency for MnOx–ZrO2/TiO2 catalytic filter could retain up to 83.2% and it could recover to 91.8% when the water vapor and SO2 were cut off. MnOx–ZrO2/TiO2 catalytic filter showed the high dust removal efficiency of 99.99% and the low filter resistance of less than 200 Pa. The filter resistance of MnOx–ZrO2 /TiO2 catalytic filter could maintain 235.7 Pa after 200 times pulse blowback. The result illustrated that MnOx–ZrO2/TiO2 catalytic filter showed good regeneration performance.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Archer Bright,Wuyi Zhang,Kaisong Xiang,Hao Chen,Hui Liu,Jun Wu
CuO-CeO 2 composite catalyst for low temperature CO oxidation was fabricated via an impregnation method. The prepared composite CuO-CeO 2 achieved 50 % and 100 % conversion at approximately ∼ 70℃ and ∼ 110℃ (denoted as T 50 and T 100 ), respectively. The enhanced catalytic activities were attributed to the formation of abundant CuO/CeO 2 heterostructures, which increased the concentration of oxygen vacancies in their lattices. In addition, the pore structure of the CuO-CeO 2 composite has also been optimized during the impregnation synthesis process. Compared with bare CeO 2 , which only possesses micropores, CuO-CeO 2 forms more mesopores on its surface, which assists in reducing the deposition rate of sulfate species on the surface. The SO 2 tolerance of the catalyst and hence its stability towards practical industrial flue gas treatment is significantly promoted. Furthermore, Density Functional Theory (DFT) was also performed to explore the mechanism of CO oxidation on the CuO-CeO 2 . It was found that the oxygen vacancy can be easily formed on the CuO/CeO 2 heterointerfaces; the adsorption energy (ΔG) of CO was therefore decreased to 0.15 eV, much lower than that of bare CeO 2 (0.53 eV). Besides, the center of f electrons of Ce in CeO 2 rises from −0.55 eV to – 1.71 eV by introducing CuO, suggesting that the f electrons in Ce become more active, which is beneficial for CO to adsorb.
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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表面化学
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工业催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2020
·
IF 3.104
Youchun Pan,Qijie Jin,Bingxu Lu,Yan Ding,Xin Xu,Yuesong Shen,Yanwei Zeng
MnCeO x /TiO 2 has been widely used in selective catalytic reduction (SCR) of NO x at low temperature. However, it is often poisoned in the presence of water vapor and sulfur dioxide . In this work, the promotion mechanism of Ba modification was investigated. Results show that the doped BaO reacts with CeO 2 and forms BaCeO 3 . This unique perovskite structure of BaCeO 3 significantly enhances NO oxidation and NH 3 activation of MnCeO x /TiO 2 catalyst so that the NO conversion and the resistances to SO 2 improve. It is found that Ba species obviously promotes the NO adsorption ability and improve the redox properties of MnCeO x /TiO 2 catalyst. While the acid properties of the catalyst are inhibited by Ba modification and among which Lewis acid sites are dominant for both MnCeO x /TiO 2 and MnCe(Ba)O x /TiO 2 catalysts. Furthermore, in situ DRIFT experiments reveal that the NO reduction upon MnCeO x /TiO 2 and MnCe(Ba)O x /TiO 2 catalysts follows both E-R and L-H mechanisms, in which L-H is preferred. Ba species enhances the formation of active nitrate species, which accelerates the NO reduction through L-H mechanism. It is interesting that although Ba species weakens the NH 3 adsorption, it induces the ammonia conversion to coordination ammonia, which in turn accelerates the catalytic reaction .
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
·
IF 5.4
Weilong Rong,Yiqing Zeng,Shule Zhang,Qin Zhong
The technology of simultaneous ammonia selective catalytic reduction (NH 3 -SCR) denitration and carbon monoxide (CO) oxidation is a proposed approach for synergistic purification of nitrogen oxides (NO x ) and CO from flue gas. However, the lack of highly efficient catalysts has hindered the widespread adoption and application of this technology. Herein, a series of CuSO 4 /TiO 2 (denoted CuS/Ti-X, X means calcination temperature at 400, 500, and 600 °C) catalysts was prepared to investigate their performance for simultaneous NH 3 -SCR denitration and CO oxidation. The results show that dispersing CuSO 4 on TiO 2 carrier induces the formation of surface Cu-O defect structure and reduces the stability of the Cu-O-S structure, which gives CuS/Ti-X catalysts a good redox property. Hence, the CuS/Ti-500 catalyst exhibits good catalytic activity in simultaneous removal of NO and CO, even in the presence of SO 2 . Reaction process investigation demonstrated that the presence of NO and NH 3 inhibits the adsorption of CO and consumes active oxygen species, thereby suppressing the CO oxidation reaction. In contrast, CO can promote the activation of NH 3 via activating the redox sites, which is conducive to the NH 3 -SCR reaction via the E-R mechanism. This study provides new insights into the strategic design of dual-functional sulfur-resistant catalysts for flue gas purification.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Yanwei Sun,Guangyan Xu,Chang Liu,Yajie Pan,Yingjie Wang,Yunbo Yu,Hong He
Although palladium-based catalysts exhibit excellent methane oxidation activity, sulfur poisoning still leads to severe deactivation. To overcome this, we synthesized an oxide-zeolite (OXZEO) composite, Ce x /Pd@MFI, via combined hydrothermal treatment and ball milling . In the resulting architecture, PdO x active sites are spatially confined within the MFI framework, while CeO 2 nanoparticles uniformly decorate the external surface as protective species. The optimized Ce 3 /Pd@MFI catalyst demonstrated markedly enhanced sulfur resistance, achieving a T 50 —the temperature at which 50 % CH 4 conversion occurred—of 361 °C after sulfation with 100 ppm SO 2 . Moreover, Ce 3 /Pd@MFI maintained sulfur-resistant stability for 110 h, far surpassing Pd@MFI and Pd/Al 2 O 3 , which rapidly deactivated upon exposure to SO 2 for bare 1 h. Furthermore, we proposed a redox-atmosphere switching method to regenerate sulfated CeO 2 protective species, thereby enabling the Ce x /Pd@MFI catalysts to maintain durable sulfur tolerance. The broad applicability of the OXZEO design was further confirmed in CO oxidation : Ce 3 /Pd@MFI remained stable under high SO 2 concentrations during CO oxidation. This work establishes a paradigm for engineering sulfur-resistant palladium catalysts via synergistic spatial confinement and protective-site incorporation, offering critical insights for the development of robust emission-control catalysts in sulfur-rich environments.
研究领域:
催化化学
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环境催化
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材料化学
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能源化学
·
大气污染控制
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Jinfeng Chen,Qingze Zhang,Yuanhong Zhong,Zhaoying Wang,Yakun Guo,Ming Sun,Lin Yu
To address the limitations of molecular sieves and metal oxides in the NH3-SCR of NOx, we synthesized a novel hybrid catalyst by integrating FeNbCe metal oxides with Cu-SSZ-13. The FeNbCe comodification significantly enhanced the low-temperature performance and sulfur resistance of Cu-SSZ-13 while maintaining 100% N2 selectivity across a broad activity window. The incorporation of Fe, Nb, and Ce reduced weak-acid and Lewis-acid sites while increasing strong Brønsted-acid sites, crucial for catalytic activity. The FeNbCe/Cu-SSZ-13 catalyst exhibited an enhanced surface oxygen content and redox capacity, promoting the “fast SCR” pathway and improving N2 selectivity at low temperatures. The FeNbCe oxides synergistically reacted with SO2, protecting Cu2+ active sites from sulfur poisoning and maintaining 100% NOx conversion for 4 h after SO2 introduction, maintaining 85% within 24 h. In situ DRIFTS characterization confirmed the dominance of the Langmuir-Hinshelwood (L-H) mechanism. The FeNbCe modification represents a significant advancement in the field of NH3–SCR catalysis, offering a practical and effective solution to enhance the performance of Cu-SSZ-13 while addressing key challenges such as sulfur resistance and low-temperature activity.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zequan Ma,Yilin Dong,Xu Tan,Jia Xue,Xiaoge Li,Yu Gu,Hui Shi,Lin-Wei Chen,Kun Wang,Lei Wang
Strong metal – support interactions represent a promising strategy to regulate catalytic performance by forming a thin encapsulation layer or new metal-bond, which have attracted explosive research attention. However, a full coating layer can sometimes block the accessibility of reactants to the active sites and significantly reduce the activity. Herein, we report a new method to construct specific PtFe/Al 2 O 3 -Fe 2 O 3 interface via tuning a relatively moderate metal-support interaction over the Al 2 O 3 -Fe 2 O 3 (AF) composite material. Our findings reveal that a permeable FeO x coating layer and PtFe alloy were formed on the Pt/AF catalysts under high temperature reduction conditions. The encapsulation layer was much thinner than that of the Pt/Fe 2 O 3 under a similar high temperature treatment. The precisely engineered Pt-Fe/AF interface presented exceptional catalytic activity for hydrogenation of cinnamaldehyde with high C=O hydrogenation selectivity (∼88 %) and impressive sulfur-resistance. This straightforward and effective approach holds significant potential value for future industrial applications.
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2021
·
IF 9.028
Xiaolei Hu,Junxiao Chen,Weiye Qu,Rui Liu,Dongrun Xu,Zhen Ma,Xingfu Tang
Although ceria-based catalysts serve as an appealing alternative to traditional V2O5-based catalysts for selective catalytic reduction (SCR) of NOx with NH3, the inevitable deactivation caused by SO2 at low temperatures severely hampers the ceria-based catalysts to efficiently control NOx emissions from SO2-containing stack gases. Here, we rationally design a strong sulfur-resistant ceria-based catalyst by tuning the electronic structures of ceria highly dispersed on acidic MoO3 surfaces. By using Ce L3-edge X-ray absorption near edge structure spectra in conjunction with various surface and bulk structural characterizations, we report that the sulfur resistance of the catalysts is closely associated with the electronic states of ceria, particularly expressed by the Ce3+/Ce4+ ratio related to the size of the ceria particles. As the Ce3+/Ce4+ ratio increases up to or over 50%, corresponding to CeO2/MoO3(x %, x ≤ 2.1) with the particle size of approximately 4 nm or less, the non-bulk electronic states of ceria appear, where the catalysts start to show strong sulfur resistance. This work could provide a new strategy for designing sulfur-resistant ceria-based SCR catalysts for controlling NOx emissions at low temperatures.
研究领域:
环境催化
·
材料化学
·
大气污染控制
·
表面科学
·
无机功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2021
·
IF 7.92
Jia-Xin He,Yong-Shan Xiao,Chang Liu,Min-Li Zhu,Yong-Hong Song,Zhong-Wen Liu
MoS 2 is an attractive sulfur-resistant catalyst for directly converting sulfur-containing syngas to high value-added chemicals. However, the effect of the layered structure on the catalytic activity for CO hydrogenation reactions is far from clear. Herein, MoS 2 /carbon composite catalysts with 1–8 stacking layers in MoS 2 crystallites are synthesized, and the impact of the layer numbers on the catalytic performance is probed for the low-temperature methanation of sulfur-containing syngas. The results indicate that the turnover frequency of CO methanation increases from 2.4 × 10 -3 to 3.7 × 10 -3 s −1 with decreasing layer numbers of MoS 2 crystallites from 8.3 to 1.1. This result is thoroughly explained by the fact that the higher ratio of rim sites in MoS 2 crystallites with fewer layer numbers enhances the catalytic activity, which originates from the facilitated activation of CO and H 2 . These understandings are important for the rational design and development of more efficient MoS 2 -based catalysts for CO hydrogenation.
研究领域:
催化
·
材料科学
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化学工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Cangpeng Shan,Qinwei Jia,Yan Zhang,Guoshuai Liu,Xinyu Hou,Yunchong Wang,Rui Han,Caixia Liu,Weichao Wang,Qingling Liu
Removing industrial source CO through catalytic oxidation and providing heat for denitrification units have significant economic and environmental benefits. Sulfur poisoning of catalysts is the bottleneck to stabilize the system operation. To overcome this problem, we fabricated sulfate modified Pt/TiO 2 by appropriate NH 4 HSO 4 deposition, which survived in the SO 2 environment with the concentration as high as 1000 ppm SO 2 , and exhibited an outstanding stability with over 90% CO conversion at 200 °C for 500 h under a typical steel sintering flue gas condition. Experimental and theoretical explorations confirmed that the electronic structure of PtO x clusters was optimized through Pt-O-S bridges after sulfate modification. The O 2p band center closer to the Fermi level and the smaller energy difference between Pt 5d and O 2p band centers led to more active lattice oxygen of PtO x clusters. The more stable π back bonding between Pt 5d and CO 2p and weaker hybridization between Pt and the π⁎ (Ssp2-Osp2)2 orbital of SO 2 indicated enhanced CO adsorption while weakened SO 2 adsorption on Pt sites. The above factors simultaneously improved the low-temperature activity and sulfur resistance for CO oxidation over sulfate modified Pt/TiO 2 . This work provides new insights for the design of sulfur-resistant catalysts and the understanding on the effect of sulfates on catalytic activity.
研究领域:
催化化学
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环境化学
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材料科学
·
化学工程
✓ 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）