ENERGY & FUELS
·
2020
·
IF 3.421
Wei Zhao,Shanshan Ruan,Siyu Qian,Beibei Feng,Chengcheng Ao,Lei Wang,Fuyi Liu,Lidong Zhang
Catalytic combustion has become a promising technology to address the accelerating volatile organic compounds (VOCs) emissions. In this work, cobalt modified ZSM-5 zeolite catalysts (3–18 wt % Co) were prepared to investigate the combustion of n-butane (one typical model component of VOCs). The performances of catalysts were evaluated by conducting experiments in a flow tube reactor. XRD, BET, FT-IR, and XPS were also utilized to characterize their physicochemical properties. A significant enhancement of the catalytic activity was demonstrated in terms of the cobalt supported over ZSM-5, with an optimal cobalt loading of 7 wt %. The excellent catalytic activity of 7 wt % Co-ZSM-5 is mainly attributed to a higher concentration of active surface Co3+ species. Furthermore, DFT calculations indicated that the role of Co can enhance the activity by decreasing the activation barriers for C–H bond cleavage. In addition, the primary reaction mechanism of n-butane combustion on Co-ZSM-5 was also revealed.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
Russian Journal of Physical Chemistry A
·
2024
·Vol. 98
·期 8
·1740-1751
·
IF 0.7
Yanliang Zhai,Lu Xianggang,Zhang Wanli,Chen Hao,Li Gaolong,Zhang Jian,Li Zhijun,Wang Jun
Abstract— Cr- and Pt-based catalysts are the most widely used industrial catalysts for propane dehydrogenation (PDH). However, these catalysts still show disadvantages such as environmental toxicity and high economic cost. Cobalt (Co)-based catalysts have become promising candidate catalysts for PDH reactions due to their environmental friendliness and low cost. In this paper, Co-based catalysts are prepared by the impregnation method and precipitation method, respectively. The obtained catalysts all show grape-like nanocrystalline aggregated structures with intercrystallite mesopores and high surface area. This can improve the dispersion of Co species and mass transfer of catalysts. Comparing catalysts prepared by the two methods, the impregnated 1CoZI sample shows smaller CoO x nanoparticle size and higher Co 2+ /Co 3+ ratio than the precipitated 1CoZP sample. Moreover, the impregnated 1CoZI sample shows higher propane conversion and propylene selectivity, which is attributed to the smaller CoO x nanoparticle size and higher content of Co 2+ species bonded with zeolite framework. This structure brings higher catalytic activity and stability to the catalyst. Different PDH reaction conditions such as the reaction temperature and propane GHSV are also investigated. Under the optimal PDH reaction conditions (525°C and 4500 h –1 ), the impregnated 1CoZI shows high propane conversion (32%) and propylene selectivity (86%).
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2022
·
IF 5.876
Haochen Qi,Chuang Xing,Weiguo Huang,Mingquan Li,Yujia Jiang,Xu Sun,Heyang Liu,Peng Lu,Jiangang Chen,Shuyao Chen
Fischer-Tropsch (FT) synthesis as a strongly exothermic reaction has diffusely manufactured clean fuels from syngas. However, it is difficult to obtain the concentrated product distributions. Here, we design ZSM-5 encapsulated cobalt particles on the thermal conductivity of the SiC matrix. The Co@NaZSM-5/SiC capsule catalyst with hierarchical structure is ingeniously assembled through a solvent-free synthesis route. Due to the joint functions of acidic zeolite , SiC thermal conductivity and macropores, the olefin selectivity enhances to 32.3% on the Co@NaZSM-5/SiC catalyst. Moreover, the ratio of O 5-11 /C 5-11 approaches 49.1% suggesting the elevated middle olefin proportion. The H + ion-exchanged Co@HZSM-5/SiC capsule catalyst shows a high isoparaffin selectivity of 27.3%, since the olefin isomerization reaction is accelerated over strong acid sites. Besides, Co 2 C phase is readily formed during the FT reaction, which is an activity center for olefin synthesis. The capsule catalyst with the proper acidity, thermal conductivity, and hierarchical structure is a promising prospect for tuning production distribution in FT reaction.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2026
·
IF 5.2
Yulin Sun,Yiwei Zhang,Yong He,Wubin Weng,Yanqun Zhu,Peixi Liu,Zhihua Wang
Mn-based catalysts usually exhibit considerable potential for enhancing the catalytic ozonation of volatile organic compounds (VOCs) at a lower temperature. In this study, bimetallic oxides M-Mn (M = Cr, Cu, Co) were supported on HZSM-5 zeolites to degrade dimethyl carbonate (DMC, chemical formula C3H6O3), a typical VOC emitted during the productive process of lithium batteries, with Mn/ZSM-5 for comparison. The Cr-doped catalyst CrMn/ZSM-5 could achieve 92% DMC conversion with 91% CO2 selectivity (O3/DMC = 6, T = 120 °C), showing an excellent catalytic performance among the prepared catalysts. The exceptionally low-temperature activity of CrMn/ZSM-5 was attributed to the synergistic effect of its large surface area, sufficient oxygen vacancies, and suitable acidity and reducibility, which collectively enhanced the level of O3 activation and accelerated DMC degradation. Furthermore, the catalyst demonstrated desirable stability and resistance to varying concentrations of water vapor. To elucidate the reaction pathway, in situ DRIFTS was employed to track the evolution of intermediate species during the adsorption and catalytic ozonation of DMC. With a further study of DFT calculation, the reaction mechanism of DMC catalytic ozonation on CrMn/ZSM-5 catalysts was put forward.
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）