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Journal of Energy Chemistry 2022年第7期31卷 224-229,I0006页

作者： Juan Du Aibing Chen College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018HebeiChina

Electrochemical reduction of CO_(2)(CO_(2)ER) to formate has been a promising route to produce value-added chemicals.Developing low-cost and efficient electrocatalysts with high product selectivity is still a grand challenge.Herein,a novel Ni nanoparticles-anchored CNT coated by mesoporous carbon with yolk-shell structure (CNT/Ni@mC) catalysis was designed for CO_(2)ER.Ni nanoparticles were confined in the cavity between CNT and mesoporous carbon shell and the confined space can be controlled by tuning the amount of silica precursor.The mesoporous carbon shell and confined space are beneficial to charge transmission during CO_(2)ER.In contrast to previous studies,the CNT/Ni@mC catalyst presents selectivity toward formate rather than CO.Electrochemical in situ attenuated total reflection Fourier transform infrared spectroscopy measurements indicate the presence of a COO* intermediate that converts to formate under CO_(2)ER conditions.The well-defined structural feature of the confined space of the Ni-based catalyst for selective CO_(2)ER to formate may facilitate in-depth mechanistic understandings on structural factors that affect CO_(2)ER performance.

关键词： Carbon dioxide electrochemical reduction nickel-based catalyst Formate Yolk-shell CNT

nickel-based Three-dimensional catalyst for Electrochemical Treatment of Urea-containing Wastewater

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Nickel-based Three-dimensional Catalyst for Electrochemical ...

Kinetics modeling for the mixed reforming of methane over Ni-CeO_2/MgAl_2O_4 catalyst

中国化学会第十九届全国催化学术会议

作者： Haitao Wang Nankai University

Urea is a nitrogen-containing fertilizer heavily used in agriculture. During the production and application of urea, huge amount of urea-rich wastewater is generated every day. Urea is also the major component of anim... 详细信息

关键词： nickel-based catalyst electrochemical treatment urea-containing wastewater

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Journal of Natural Gas Chemistry 2011年第1期20卷 9-17页

作者： Hye Jin Jun Myung-June Park Seung-Chan Baek Jong Wook Bae Kyoung-Su Ha Ki-Won Jun Department of Chemical Engineering Ajou University Petroleum Displacement Technology Research Center Korea Research Institute of Chemical Technology (KRICT)

Kinetics model was developed for the mixed （steam and dry） reforming of methane, which is useful for the control of H2/CO ratio. The equilibrium constants of reaction rate were determined using the experimental equilibrium data at different reaction temperatures, while the forward reaction rate constants were estimated using the experimental data under non-equilibrium （high inert fraction and high space velocity） conditions. The comparison between calculated and experimental data clearly showed that the developed model described satisfactorily, and further analysis using the parametric sensitivity determined the wall temperature and CO2 fraction in the feed gas as effective parameters for the manipulation of CH4 conversion and H2/CO ratio of synthesis gas under the equilibrium condition. Meanwhile, the inert fraction, rather than the residence time, was selected as additional parameter under non-equilibrium condition.

关键词： mixed reforming nickel-based catalyst kinetics modeling parameter estimation parametric sensitivity

Effect of CeO_2 and CaO Promoters on Ignition Performance for Partial Oxidation of Methane over Ni/MgO-Al_2O_3 catalyst

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Journal of Natural Gas Chemistry 2007年第2期16卷 148-154页

作者： Yejun Qiu Jixiang Chen Jiyan Zhang Department of Catalysis Science and Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

The effect of CeO2 and CaO promoters on the ignition performance over Ni/MgO-Al2O3 catalyst for the partial oxidation of methane （POM） to synthesis gas was investigated. It was found that the POM reaction could not be ignited over lwt%Ni/MgO-Al2O3 catalyst without the promoters in the temperature range from 773 K to 1073 K. CeO2 and CaO promoters enhanced the ignition performance and the POM reactivity of lwt%Ni/MgO-Al2O3 catalyst remarkably. Moreover, the improving effect became greater with the increase of the promoter content under the investigated reactiorrconditions. The modification effects of CeO2 and CaO promoters were closely related to the concentration and reducibility of the surface and bulk oxygen species.

关键词： partial oxidation of methane synthesis gas nickel-based catalyst ignition cerium oxide calcium oxide

Modification of Ni/SiO_2 catalysts by Means of a Novel Plasma Technology

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Plasma Science and Technology 2008年第5期10卷 551-555页

作者：李育亮刘改焕宋磊储伟戴晓雁印永祥 Department of Chemical Engineering Sichuan UniversityChengdu 610065China

Atmospheric high frequency cold plasma jet was applied to modify Ni/SiO2 catalysts. The catalysts prepared by two different methods with plasma jet were compared with conventional catalysts. BET, XRD, H2-TPD and high-resolution transmission electron microscopy （HRTEM） were used to characterize these catalysts. The results showed that the catalyst prepared with plasma jet had higher nickel dispersion, larger specific surface area and smaller nickel particle size, about 5 nanometres. Detailed analyses revealed that improved structure and characteristic of the plasma catalyst were benefited from the large amount of hydrogen atoms in the plasma jet, by which the catalyst reduction can be easily achieved in shorter period of time at lower temperature, thus avoiding sintering and conglomeration of the active particles and the support. The activity of catalysts was investigated in the methane reforming with CO2. It is shown that the conversions of CH4 and CO2, the yields of H2 and CO were all significantly increased for the plasma catalysts.

关键词： plasma-reduced nickel-based catalyst silica gel support low-temperature activity methane reforming with carbon dioxide

Effects of preparation methods of support on the properties of nickel catalyst for hydrogenation of m-dinitrobenzene

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Frontiers of Chemical Science and Engineering 2007年第3期1卷 287-291页

作者： LIU Yingxin WEI Zuojun CHEN Jixiang ZHANG Jiyan Department of Catalysis Science and Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Zhejiang University of TechnologyHangzhou 310032China Institute of Pharmaceutical Engineering College of Materials Science and Chemical EngineeringZhejiang UniversityHangzhou 310027China

Using tetraethyl orthosilicate(TEOS)as the pre-cursor of silica,the silica aerogel and xerogel,which were used as supports of nickel-based catalysts for liquid hydroge-nation of m-dinitrobenzene to m-phenylenediamine,were prepared by the sol-gel method combined with supercritical drying(SCD)and conventional drying,respectively.Then,a series of nickel-based catalyst samples supported on these supports were prepared by the incipient wetness impregna-tion method with an aqueous solution of nickel nitrate as well as lanthanum nitrate as impregnation liquids.based on the characterization results of nitrogen adsorption-desorption(BET),X-ray diffraction(XRD),temperature programmed reduction(TPR),temperature-programmed desorption of hydrogen(H2-TPD),and catalytic activity evaluation,the physico-chemical properties and catalytic performances of the catalysts were investigated.The results show that the nickel crystallites on the binary nickel catalyst using silica aerogel as support are of smaller particle size.However,com-pared with the sample supported on silica xerogel,the nickel catalyst supported on the silica aerogel exhibits lower activity and selectivity for the hydrogenation of m-dinitrobenzene because it has a lesser amount of active sites and weaker absorption ability to reactants caused by sintering of the nickel crystallites.The addition of promoter La2O3 could increase the activity and selectivity of the catalysts.Among all the nickel-based catalyst samples prepared,the La2O3 promoted ternary nickel-based catalyst supported on silica xerogel exhibits the highest activity and selectivity for the hydrogenation of m-dinitrobenzene to m-phenylenediamine,which could be attributed to its highest active surface area and appropriate absorption strength to reactants.Over this prom-ising catalyst,the conversion of m-dinitrobenzene and the yield of m-phenylenediamine could reach 97.0%and 93.1%,respectively,under proper reaction conditions of hydrogen pressure 2.6 MPa,temperature 373 K,and reaction time 1 h.

关键词： sol-gel method supercritical drying nickel-based catalyst lanthanum oxide hydrogenation m-dinitrobenzene m-phenylenediamine

Autothermal Reforming of Methane over Ni catalysts Supported on CuO-ZrO_2-CeO_2-Al_2O_3

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Journal of Natural Gas Chemistry 2006年第2期15卷 122-126页

作者： Xiulan Cai Xinfa Dong Weiming Lin School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China

Ni catalysts supported on various mixed oxides of Al2O3 with rare earth oxide and transitional metal oxides were synthesized. The studies focused on the measurement of the autothermal reforming of methane to hydrogen over Ni catalysts supported on the mixed oxide ZrxCe30-xAl70Oδ （x-=5, 10, 15）. The catalytic performance of Ni/Zr10Ce20Al70Oδ was better than that of other catalysts. XRD results showed that the addition of Zr to Ni/Ce30Al70Oδ prevented the formation of NiAl2O4 and facilitated the dispersion of NiO. Effects of CuO addition to Zr10Ce20Al70Oδ were also investigated. The activity of Ni catalyst supported on CuO-ZrO2-CeO2-Al2O3 was somewhat affected and the Ni/Cu5Zr10Ce20Al65Oδ showed the best catalytic performance with the highest CH4 conversion, yield of H2, selectivity for H2 and H2/CO production ratio in operation temperatures ranging from 650 to 750 ℃.

关键词： methane autothermal reforming hydrogen nickel-based catalyst ceria zirconia promoter

Methane Decomposition into Carbon Fibers over Coprecipitated nickel-based catalysts

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Journal of Natural Gas Chemistry 2005年第2期14卷 101-106页

作者： YanJu FengyiLi RenzhongWei DepartmentofChemistry NanchangUniversityNanchang330047China

Decomposition of methane in the presence of coprecipitated nickel-basedcatalysts to produce carbon fibers was investigated. The reaction was studied in the temperaturerange of 773 K to 1073 K. At 1023 K, the catalytic activities of three catalysts kept high at theinitial period and then decreased with the reaction time. The lifetimes of Ni-Cu-Al and Ni-La-Alcatalysts are longer than that of Ni-Al catalyst. With three catalysts, the yield of carbon fiberswas very low at 773 K. The yield of carbon fibers for Ni-La-Al catalyst was more than those forNi-Al and Ni-Cu-Al catalysts. For Ni-La-Al catalyst, the elevation of temperature from 873 K up to1073 K led gradually to an increase in the yield of carbon fibers. XRD studies on the Ni-La-Alcatalyst indicate that La_2NiO_4 was formed. The formation of La_2NiO_4 is responsible for theincrease in the catalytic lifetime and the yield of carbon fibers synthesized on Ni-La-Al at773-1073 K. Carbon fibers synthesized on Ni-Al catalyst are thin, long carbon nanotubes. There arebamboo-shaped carbon fibers synthesized on Ni-Cu-Al catalyst. Carbon fibers synthesized on Ni-La-Alcatalyst have large hollow core, thin wall and good graphitization.

关键词： methane decomposition carbon fibers nickel-based catalyst