Journal of CO2 Utilization
·
2022
·
IF 8.321
Yutong Shen,Jun Xiao,Qijing Wu,Jingting Su,Li Zhu
To improve the conversion efficiency and reduce the CO 2 emissions associated with the reforming of biomass tar to syngas, photothermal catalysts were prepared in this study through various impregnation methods. Photothermocatalytic CO 2 reforming (PTCR) of benzene as a tar model compound, was conducted using the prepared Ni/TiO 2 -Al 2 O 3 catalysts. The results show that the introduction of TiO 2 facilitates the conversion of NiO to Ni during the photothermal reaction, while the photocatalysis of TiO 2 significantly enhances the photothermocatalytic activity of the Ni/Al 2 O 3 catalysts at low temperatures. Moreover, the methodology for catalyst preparation involving the loading of NiO before TiO 2 is also beneficial to catalyst performance. However, when the mass ratio of TiO 2 to Al 2 O 3 exceeds 1, the specific surface area, pore volume, and structural stability of the catalysts are reduced. The results of PTCR experiment show the following optimal Ni/TiO 2 -Al 2 O 3 catalyst preparation parameters: 25% NiO content and a TiO 2 /Al 2 O 3 ratio of 3:7; 450 °C calcination temperature and a nitrogen atmosphere. The maximum benzene conversion achieved through PTCR with the 0.25Ni/0.3Ti0.7Al(M2) catalyst is 88.2%. However, a large amount of coke is deposited onto the spent catalyst surface, contributing significantly to catalyst deactivation.
研究领域:
能源化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Changzhen Wang,Hao Wu,Xiangyu Jie,Xiaoming Zhang,Yongxiang Zhao,Benzhen Yao,Tiancun Xiao
Well-geometric-confined yolk–shell catalysts can act as nanoreactors that are of benefit for the antisintering of metals and resistance to coke formation in high-temperature reactions such as the CO2 reforming of methane. Notwithstanding the credible advances of core/yolk–shell catalysts, the enlarged shell diffusion effects that occur under high space velocity can deactivate the catalysts and hence pose a hurdle for the potential application of these types of catalysts. Here, we demonstrated the importance of the shell thickness and porosity of small-sized Ni@SiO2 nanoreactor catalysts, which can vary the diffusional paths/rates of the diffusants that directly affect the catalytic activity. The nanoreactor with an ∼4.5 nm shell thickness and rich pores performed the best in tolerating the shell diffusion effects, and importantly, no catalytic deactivation was observed. We further proposed a shell diffusion effect scheme by modifying the Weisz–Prater and blocker model and found that the “gas wall/hard blocker” formed on the openings of the shell pores can cause reversible/irreversible interruption of the shell mass transfer and thus temporarily/permanently deactivate the nanoreactor catalysts. This work highlights the shell diffusion effects, apart from the metal sintering and coke formation, as an important factor that are ascribed to the deactivation of a nanoreactor catalyst.
研究领域:
化学工程
·
材料科学
·
催化反应
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Liang Wang,Jinqiang Zhang,Jun Huang,Qun Cui,Yuezhao Zhu,Haijun Chen
Supported Ni and Ir nanocatalysts have been used in CO2 dry reforming of methane (DRM); however, their fast deactivation limited further applications. In this research, we introduced NiO nanoparticles (NPs) on the SiO2 surface ahead of the addition of the Ir source for the bimetallic Ir–Ni/SiO2 catalyst. The homogeneous NiO NPs provide finite spaces to prohibit the agglomeration of Ir NPs under H2 reduction. The Ir–Ni/SiO2 catalyst was obtained with ultrasmall bimetallic NPs (1.4 nm) uniformly distributed on the SiO2 surface. Owing to the synergistic effects within the bimetal, the catalytic performance on the fabricated bimetallic catalyst into the DRM reaction is significantly enhanced, with 1.2 times higher than the sum of the Ir and Ni monometallic catalysts. Besides, the side reaction of the reverse water–gas shift reaction is effectively suppressed, and the stability is also improved. This facile strategy provides another approach to fabricate ultrasmall and homogeneous bimetallic catalysts for efficient storage and conversion of fossil fuels.
研究领域:
化学工程
·
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2024
·Vol. 154
·期 7
·3829-3838
·
IF 2.3
Wang Mingyue,Li Ting,Tian Yuhao,Zhang Jiarong,Cai Weijie
To develop high-performance catalysts for greenhouse gas CO 2 reforming with ethanol (EDR) is progressively inspired by the urgent requirement of CO 2 elimination in order to meet with the sustainable development. In this work, the bimetallic Co(Ni)/ZnO catalyst derived from MOFs was investigated in detail with a focus on the effect of Ni dopant. The EDR results indicated that the bimetallic Co(Ni)/ZnO catalyst presented better activity as well as less formation of byproducts in comparison with the monometallic Co/ZnO catalyst. 100% of ethanol conversion was obtained at 500 °C for Co(Ni)/ZnO versus 650 °C for Co/ZnO. Moreover, no acetone formation was observed over Co(Ni)/ZnO catalyst while the concentration of acetone in Co/ZnO was as high as 10 mol%. Characterization results depicted that the strong synergistic effect between Ni and Co in Co(Ni)/ZnO catalyst might greatly stabilize active metal cobalt with smaller particle size, improve the reducibility and facilitate the generation of oxygen defects, thereby enhancing the catalytic performance. To a certain extent, this work might contribute to the design of efficient catalysts for other catalytic applications. Graphical
研究领域:
催化
·
环境化学
·
材料科学
·
绿色化学
·
能量转换
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Xiaodi Zhang,Guojie Zhang,Xiaowei Qin,Jun Liu,Guoqiang Li,Ying Xu,Yongkang Lv
A series of nitrogen doped biomass carbon catalysts were prepared through two different nitrogen doped methods by using soybean meal as the raw material, melamine as nitrogen source and KOH as the activators. The catalysts were characterized by BET, SEM , CO 2 -TPD, EA , FTIR , XPS and Raman. The catalytic performances of CH 4 –CO 2 reforming over different samples were also studied. The results show that the preparation method of the catalyst significantly affects the structural characteristics, N content and N species type of the catalyst. The characterization results also show the proportion of pyrrolic-N in the catalyst prepared by in-situ nitrogen doped method (Y-NC) is higher than that in prepared by the post-treatment method (H-NC). Pyrrole-N is more conducive to the adsorption and activation of CO 2 . So, the catalyst prepared by in-situ nitrogen doped method has good catalytic activity and stability. The conversion of CH 4 and CO 2 were respectively 40% and 65% at 900 °C after 50 h of CH 4 –CO 2 reforming reaction .
研究领域:
催化
·
材料科学
·
环境科学
·
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）