FUEL
·
2023
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IF 7.4
Yang Du,Shi-Qi Yang,Yun-Jie Li,Zhi-Bin Wang,Xing-Bao Wang,Zhen-Yi Du,Wen-Ying Li
Nickel-based catalysts have been broadly studied for the steam reforming of coal/biomass tar due to their inexpensiveness and good activity. Nevertheless, their industrial application has long been restricted by the deactivation induced by carbon deposition and Ni sintering in the reforming process. Herein, ordered mesoporous nickel-alumina catalysts with varying K contents were prepared. Their performance in steam reforming of toluene as a model compound of tar was evaluated to reveal the effects of K doping. Among them, the catalyst with 2 wt% K loading displayed the best catalytic activity and stability. Experimental and theoretical calculation results suggested that K doping enhances the water adsorption capability of the catalysts, which thereby reduces the amount and graphitization degree of carbon deposits. Moreover, the K doping reduces the acid amount of the support and thereby inhibits the formation of carbon deposits as well. However, K doping does not affect the reaction pathway of the catalysts in toluene steam reforming, and the main reaction intermediates detected with in-situ DRIFTS remain the carbonate groups. Furthermore, the confinement effects of the ordered mesoporous structures inhibit the sintering of Ni particles and the formation of carbon deposits. In addition, the influence of different spatial positions of K on the catalysts was explored. It was found that the K introduction via the one-pot solvent evaporation induced self-assembly method can suppress the loss of K from the catalysts.
研究领域:
催化
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Xueyu Hu,Jian Zhang,Yihan Liu,Tiancheng Wen,Xiaohong Yao,Chao Long
The non-thermal plasma catalysis holds great promise for VOCs removal, and the development of catalysts with electronic metal-support interaction (EMSI) effect is beneficial for VOCs removal. In this study, we prepared three Mn@M catalysts with EMSI coordination structures by encapsulating MnO x particles within the mesoporous molecular sieve (MCM-41) with different pore size (2.9 nm, 4.4 nm, and 7.9 nm), and investigated the effect of pore size on EMSI and non-thermal plasma catalytic performance of Mn@M for toluene. Among three catalysts, Mn@M2 with an average pore size of 4.38 nm exhibited the strongest EMSI and superior redox capabilities, thus demonstrating the highest mineralization rate, carbon balance, and CO 2 selectivity for plasma catalytic oxidation of toluene. The EMSI effect leads to the formation of electron-rich and electron-poor centers on the Si-O-Mn-O bond, facilitating the generation of reactive oxygen species and enhancing the oxygen cycle. In addition, the reaction degradation pathway was investigated using in situ DRIFTS and GC–MS. This study provides valuable insights for designing highly effective supported catalysts by pore confinement to degrade VOCs in adsorption-plasma catalysis system.
研究领域:
环境科学
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催化
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2022
·
IF 8.047
Minjie Xu,Xianglin Liu,Guiyao Song,Yingying Cai,Bianfang Shi,Yitao Liu,Xiaoxu Ding,Zixu Yang,Pengfei Tian,Chenxi Cao,Jing Xu
Different iron species exhibit distinct activity and selectivity in CO 2 hydrogenation reaction. Herein, by controlling calcination temperature, Fe-Al interaction in Na promoted Fe-Al catalysts has been regulated, which further leads to various compositions of iron oxide (FeO x ) and iron carbides (Fe 7 C 3 and Fe 5 C 2 ) after CO activation and CO 2 hydrogenation reaction. The phase compositions and structures of Fe-Al catalysts are carefully distinguished by multiple characterizations, including XRD, XPS, MES and TEM, and the reactivity of different phases is studied with the combination of experiments (kinetics, TP and in situ DRIFTS) and Density Functional Theory (DFT) calculations. Our FeAl350 with the highest FeC x content shows the highest CO 2 conversion of 48.2% and the lowest CO selectivity of 10.1%, and FeAl900 with the highest Fe 5 C 2 / FeC x ratio presents the highest C 5+ selectivity of 44.6%. Finally, a correlation between different compositions of iron species with the activity and selectivity of Fe-based for CO 2 hydrogenation to olefins was established.
研究领域:
催化
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化学工程
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材料科学
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Qilong Chen,Dezhen Zhang,Tao Wei,Zicheng Wang,Shangpu Zhuang,Xu Qiao,Zhuxiu Zhang
Polycyclic aromatic hydrocarbons (PAHs) are toxic environmental contaminants presented in most of environmental matrices. The mullite and Fe 2 O 3 were identified as the reactive species of coal fly ash for the cracking-oxidation of PAHs (3∼5 benzene rings, e.g., anthracene, pyrene, benzo(a)pyrene). The conversion of PAHs reached over 99 % at 250–300 ℃ with the non-methane total hydrocarbons (NMHC) in the off-gas being below 50 mg/m 3 . The in-situ DRIFTS and TGA/GC–MS revealed the synergy of Brønsted acid sites from mullite and oxidation active sites from Fe 2 O 3 for the pyrene decomposition. The reaction process was initiated by self-condensation of a minor fraction of pyrene that provide hydrogen radicals to convert remaining pyrene to dihydropyrene. Then dihydropyrene underwent a series of Brønsted acid-catalyzed β-scission and alkyl transfer reactions to form light hydrocarbons that were then converted to CO 2 and H 2 O over Fe 2 O 3 species. The cracking-oxidation of PAHs were furtherly verified in terrestrial/aqueous systems which is known as the most common environment matrices of PAHs. A demonstrative equipment comprised of a riser-downer reactor was used for such cracking-oxidation process to ensure particle fluidization, mass transfer and circulation efficiency. PAHs can be almost completely removed from the environment matrices with the NMHC concentration of 46.3–49.6 mg/m 3 in the off-gas and COD of 0.6–4.1 mg/L in the condensate water. The energy released from the exothermic cracking-oxidation reaction was re-utilized to heat the feed air, so the energy consumption and related operation cost outperformed those of traditional methods.
研究领域:
环境科学
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化学工程
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分析化学
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能源技术
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污染控制
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
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2025
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IF 7.2
Jiaman Wang,Jing Xiong,Zekai Cui,Yuanfeng Li,Hao Guo,Guilin Liu,Yaxiao Ma,Linsheng Xu,Jinqing Jiao,Jianping Zou,Yuechang Wei
CeO 2 , a pivotal rare earth oxide in environmental catalysis, has garnered extensive interest for soot oxidation owing to its exceptional oxygen storage capacity and oxygen vacancy-rich surfaces. To further optimize catalytic efficiency, we engineered spherical CeO 2 with exposed (111) facets via hydrothermal synthesis and uniformly anchored Pd species through a gas bubbling-assisted membrane reduction (GBMR) strategy. The formation of Pd–O–Ce interfacial units is identified as critical active sites, where metal-support interaction (MSI) significantly enhances oxygen transfer. Notably, the Pd 1.0 /CeO 2 catalyst achieves a remarkable T 50 of 356 °C (14% lower than pristine CeO 2 ), attributed to highly dispersed Pd species and abundant Pd–O–Ce interfaces. In contrast, excessive Pd species loading induces particle agglomeration, weakening MSI effect and catalytic performance. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional thoery (DFT) calculations reveal that the Pd–O–Ce interface promotes NO adsorption – the rate limiting step – by generating electron-rich Pd sites and oxygen vacancies, thereby accelerating NO-to-NO 2 conversion and subsequent soot oxidation. This work highlights the pivotal role of interfacial engineering in optimizing Pd–CeO 2 catalysts, offering a rational design strategy for high-performance soot oxidation systems in diesel emission control.
研究领域:
环境催化
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材料科学
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多相催化
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排放控制
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纳米材料
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
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2025
·
IF 3.5
Li Xinyu,Li Jingqi,Li Na
This study investigated the effects of sequential acid treatment and phosphorus incorporation on the performance of Fe–Mn-Ce composite metal oxide catalysts. The FeMnCeO x catalyst was prepared using the sol–gel method and modified through two methods: treatment with phosphoric acid alone and a sequential treatment with phosphoric acid followed by sulfuric acid. The results show that the sequentially acid-treated catalyst exhibited over 90% NO x conversion and N 2 selectivity in the temperature range of 200–350 °C, outperforming other catalysts. Characterization analyses such as XRD and NH 3 -TPD revealed that acid modification enhanced the surface acidity and redox properties of catalysts. XPS analysis showed that sequential acid treatment increased the surface chemisorbed oxygen content of the catalyst and optimized its surface structure. In-situ DRIFTS spectroscopy further elucidated that the catalytic reaction follows both Langmuir–Hinshelwood and Eley–Rideal mechanisms concurrently.
研究领域:
环境科学
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催化化学
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材料科学
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化学工程
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2022
·
IF 6.76
Shuangde Li,Tao Wang,Mu Zhou,Shaohua Chai,Linfeng Nie,Zhenjiang Wu,Ning Han,Yunfa Chen
A dual-functional adsorption–catalytic system for elimination of trace toluene is developed and realized over molecular sieve-hosted varied ratio of platinum and palladium catalysts. PtPd/molecular sieve exhibites PdO and PtO 2 around 2–3 nm particles with uniform loading verified by XRD, TEM, Raman and XPS. The adsorption–desorption–catalysis for trace toluene purification is evaluated on the quartz micro-reactor and the self-made electrically heated equipment. 3Pt1Pd/molecular sieve shows toluene adsorption capacity of 18.22 mg/g and desorption efficiency about 77%, together with the maximum desorption temperature at 100 °C. 3Pt1Pd/molecular sieve owns toluene conversion with 38.3% and 100% at 100 and 200 °C, accompanied with the higher CO 2 selectivity of 0.0% and 150.0%, separately, due to the higher Pd 2+ content. The catalyst displays water vapor endurance, reproducibility, and 83.0% carbon balance during the whole adsorption–desorption–catalysis within 150 min, which highlights the sustainable applicability in lean VOCs abatement. Furthermore, the possible catalytic reaction pathway of toluene oxidation is proposed based on the in-situ DRIFTS experiments.
研究领域:
环境科学
·
催化
·
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）