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Influence of MgO contents on silica supported nano-size gold catalyst for carbon monoxide total oxidation

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Journal of Natural Gas Chemistry 2011年第5期20卷 498-502页

作者： huiyuan xu Weiyi Li Shuyong Shang Chunrong Yan Department of Chemical Engineering Yibin University Yibin 644000 Sichuan China Department of Chemical Engineering Stchuan University Chengdu 610065 Sichuan China

A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and property of the nano-size gold catalysts were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, O2 temperature-programmed desorption （O2-TPD）, and inductively coupled with plasma atomic emission spectroscopy （ICP-AES） techniques. The total oxidation of CO was chosen as the probe reaction. The results suggest that for the gold catalysts supported on the silica material after MgO modification, the size of the gold particles is pronouncedly reduced, the oxygen mobility is enhanced, and the catalytic activity for low-temperature CO oxidation is greatly improved. The gold catalyst modified by 6 wt% MgO （Mg/SiO2 weight ratio） shows higher CO oxidation activity, over which the temperature of CO total oxidation is lower about 150 K than that over the silica directly supported gold catalyst.

关键词： new nano-size gold catalyst CO oxidation MgO SiO2 structure activity relationship

Effects of impregnation sequence on the microstructure and performances of Cu-Co based catalysts for the synthesis of higher alcohols

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Journal of Natural Gas Chemistry 2008年第4期17卷 369-373页

作者： Siyu Deng Wei Chu huiyuan xu Limin Shi Lihong Huang Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China

Silica-supported CuCo catalysts were prepared by impregnation method with different impregnation sequence for higher alcohols synthesis. These catalysts were characterized by H2-TPR, XRD, N2 adsorption, XPS techniques and CO selective hydrogenation reaction measurement. The effects of impregnation sequence on the structure and performance of catalysts were investigated, and there were important influences on the selectivity to higher alcohols. There was a strong synergistic effect between copper and cobalt for the co-impregnated sample. The CuCo/SiO2 catalyst prepared by co- impregnation showed a better yield of total alcohols, and a higher selectivity to total alcohols which reached 51.5%.

关键词： copper cobalt impregnation sequence synergistic effect selective hydrogenation carbon monoxide

Low-temperature CO oxidation over CuO-CeO_2/SiO_2 catalysts:Effect of CeO_2 content and carrier porosity

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Journal of Natural Gas Chemistry 2010年第4期19卷 355-361页

作者： Jingjie Luo Wei Chu huiyuan xu Chengfa Jiang Tao Zhang Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China

The effects of CeO2 contents and silica carrier porosity with their pore diameters ranging from 5.2 nm to 12.5 nm of CuO-CeO2/SiO2 cata-lysts in CO oxidation were *** catalysts were characterized by N2 adsorption/desorption at low temperature,X-ray diffraction （XRD）,temperature-programmed reduction by H2 （H2-TPR）,oxygen temperature programmed desorption （O2-TPD） and X-ray photoelectron spectroscopy （XPS）.The results suggested that,the ceria content and the porosity of SiO2 carrier possessed great impacts on the structures and catalytic performances of CuO-CeO2/SiO2 *** appropriate content of CeO2 （Ce content 8 wt%） was added,the catalytic activity was greatly *** the catalyst supported on silica carrier with larger pore diameter,higher dispersion of CuO was observed,better agglomeration-resistant capacity was displayed and more lattice oxygen could be found,thus the CuO-CeO2 supported on Si-1 showed higher catalytic activity for low-temperature CO oxidation.

关键词： CuO-CeO2 based catalyst silica carrier porosity carbon monoxide oxidation O2-TPD

Ni/MgO catalyst prepared using atmospheric high-frequency discharge plasma for CO_2 reforming of methane

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Journal of Natural Gas Chemistry 2011年第5期20卷 487-492页

作者： Pan Qin huiyuan xu Huali Long Yi Ran Shuyong Shang Yongxiang Yin Xiaoyan Dai Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China Department of Chemical Engineering Yibin University Yibin 644000 Sichuan China

A new type of Ni/MgO catalyst was prepared using atmospheric high-frequency discharge cold plasma. The influences of conventional method, plasma method, and plasma plus calcination method on the catalytic activity were studied and the CO2 reforming of methane was chosen as the probe reaction. The catalysts were characterized by X-ray diffraction （XRD）, transmission electron microscope （TEM）, X-ray photoelectron spectroscopy, and CO2 temperature-programmed surface reaction techniques. The results suggested that the nickel-based catalyst prepared by plasma plus calcination method possessed a smaller particle size and a higher dispersion of active component, better low-temperature activity and enhanced anti-coking ability. The conversion of CO2 and CH4 was 90.70% and 89.37%, respectively, and the reaction lasted for 36 h without obvious deactivation under 101.325 kPa and 750°C with CO2/CH4 = 1/1.

关键词： Ni/MgO catalyst carbon dioxide methane reforming atmospheric high-frequency discharge cold plasma

Organic-Inorganic Interaction Recorded by Polycyclic Aromatic Steranes in Continental Epithermal Ore Deposits

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 327-336页

作者： xu huiyuan LIU Quanyou JIN Zhijun ZHU Dongya MENG Qingqiang LI Pengpeng ZHU Biqing State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China Petroleum Exploration&Production Research Institute SINOPECBeijing 100083China Institute of Energy School of Earth cand Space SciencesPeking UniversityBeijing 100871China

Continental epithermal ore deposits are commonly associated with sedimentary organic matter,oils or solid *** organics embedded in mineral deposits can convey valuable information of the ore ***,the extent to which the formation of ore minerals was recorded by organic compounds remains largely unknown,as also is how metal-rich ores interfere with the molecular proxies in the temperature regime envisaged for hydrothermal *** molecular compositional changes of various polycyclic aromatic steranes and polycyclic aromatic hydrocarbons and compounds derived from the Jinding Pb/Zn deposit,SW China provide new *** regular steranes are present as *** transformation from polycyclic aromatic steranes to unsubstituted polycyclic aromatic hydrocarbons is observed to show an increased trend with increasing hydrothermal alteration levels;this is consistent with the transformation from unsubstituted polycyclic aromatic hydrocarbons to heterocyclic ***(aromatization)of polycyclic biological compounds and hydrodecyclization(dearomatization)of polycyclic aromatic compounds are two important reaction pathways in hydrothermal systems with moderate *** detailed investigation of organicinorganic interactions of two groups of polycyclic compounds with metal-rich ores provides insights into the questions on how and to what extent the formation of Pb/Zn deposits can be recorded by *** work will improve our understanding of carbon reduction,oxidation or condensation in the deep Earth and the carbon exchange between the Earth's crust and mantle,and may shed light on the processes for ultra-deep hydrocarbon exploration.

关键词： petroleum resources organic-inorganic interaction biomarker polycyclic compounds hydrothermal environment

Effect of Fe content on FeMn catalysts for light alkenes synthesis

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Frontiers of Chemical Science and Engineering 2008年第3期2卷 315-318页

作者： Jun ZHOU Wei CHU Hui ZHANG huiyuan xu Tao ZHANG College of Chemical Engineering Sichuan UniversityChengdu 610065China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

The effect of Fe content on FeMn/MgO catalysts for light alkenes synthesis through CO hydrogenation was *** were prepared by a conventional co-impregnation method,characterized using BET,X-ray powder diffraction(XRD)and Temperature-programmed reduction(H_(2)-TPR)*** activity was obtained over the catalyst with 9 wt-%Fe content,over which CO conversion and the selectivity of C2^(=)-C4^(=)reached 91.36%and 58.48%,*** the increase of Fe content,both the conversion and the selectivity were improved within a certain range and then *** results show that the surface area of the catalyst played an important role in the catalytic *** the increase of Fe loading,the interaction action between Fe and Mn was enhanced and FeMn solid solution was formed.

关键词： Fe content FeMn/MgO catalyst light alkenes CO hydrogenation

Tuning redox activity through delithiation induced protective layer and Fe-O coordination for Li-rich cathode with improved voltage and cycle performance

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Journal of Energy Chemistry 2022年第8期31卷 266-276,I0008页

作者： Kanghui Hu Li Ren Weifeng Fan Bing Zhang Meihua Zuo Yanhui Zhang Genpin Lv huiyuan xu Wei Xiang Xiaodong Guo College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059SichuanChina Yibin Libode New Materials Co. Ltd.Yibin 644200SichuanChina Shaoguan HEC Technology R&D Co. Ltd.Ruyuan 512000GuangdongChina Yibin Tianyuan Grp Co. Ltd.Yibin 644200SichuanChina School of Chemical Engineering Sichuan UniversityChengdu 610065SichuanChina

Li-rich layered transition metal oxides are one of the most promising cathode materials for their high energy ***,the cathodes usually suffer from severe potential dropping and capacity fading during cycling,which are associated with the surface oxygen release and accompanied by cation densification and structural ***,an integrative approach of simultaneous constructing uniform 3d Fe-ion doping in the transition metal layer and Li-rich Li_(5)FeO_(4) shell to grab the oxygen and prevent interfacial side reactions is *** introduction of Fe induces higher redox potential and stronger 3 d Fe-O_(2)p covalent bond,triggering reversible anionic redox via a reductive coupling *** the delithiated product of Li-rich Li_(5)FeO_(4) not only acts as a protective layer alleviating the side reactions but also enhances the surface kinetic *** the benefit of promoted reversibility of oxygen redox and enhanced surface stability,the cathode exhibits high reversible capacity and superior cycle *** function theory calculation indicates that the O_(2)p non-bonding state in the cathode incorporated with Fe sits at a lower energy band,resulting in higher energy storage voltage and improved oxygen ***,the modified cathode exhibits a discharge specific capacity of 307 m A h g^(-1)(1 C=250 m A g^(-1)),coulombic efficiency of 82.09%in the initial cycle at 0.1 C and 88.34%capacity retention after 100 cycles at 1 *** work illustrates a strategy that could simultaneously enhance oxygen redox reversibility and interface stability by constructing lattice bond coordination and delithiation induced protective layer to develop Li-rich materials with high reversible capacity and long lifespan.

关键词： Li-rich cathode Lattice oxygen evolution Tuning redox activity Interface modification

Promoter effect of La2O3 on gold catalyst with different textural structures

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Journal of Energy Chemistry 2016年第5期25卷 854-860页

作者： huiyuan xu Jingjie Luo Shenying xu Denglei Zhu Wei Chu Department of Chemical Engineering Yibin UniversityYibin 644000 SichuanChina Department of Chemical Engineering Sichuan UniversityChengdu 610065SichuanChina

Silica supported gold nanoparticles were synthesized and promoted by lanthanum oxide as dopant. The influences of LaOand silica textural structure on the gold dispersion, formation of active species, crystalline composition and the reacting role of dopants were studied in detail. The characterization results suggested that the dispersion of gold nanoparticles depended on the textural structure of silica without lanthanum oxide doping where small mesopores are more preferable to disperse gold nanoparticles. The addition of lanthanum oxide largely increased the dispersion of gold nanoparticles and oxygen active sites independent of the textural structure of silica support. The interaction between lanthanum oxide and silica enhanced by the synergy facilitated the release of oxygen vacancies and transition of active oxygen species. In addition, the chemical properties were greatly changed after lanthanum oxide addition which was only inconspicuously impacted by the initial textural structure of silica supports, shedding light on the further design of economic gold catalyst based on simple synthesis method.

关键词： Gold catalysis Catalyst design Au-metal synergy CO oxidation

Diamondoids in petroleum: a review of sources and thermal evolution

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Journal of Earth Science 2024年

作者： Biqing Zhu Quanyou Liu huiyuan xu Dongya Zhu Qingqiang Meng Jingbin Wang Institute of Energy， Peking University Petroleum Exploration and Production Research Institute SINOPEC

Cage structural diamondoids serve as highly stable molecular indicators， extensively employed in delineating the hydrocarbon sources， particularly in light oils and condensates found in ultra-deep reservoirs. A systematic summary of thermal pyrolysis experiments suggested that the thermal evolution of diamondoids in petroleum consists of four distinct stages: (1) birth， (2) growth and enrichment， (3) decrease and decomposition， and (4) complete decomposition. The diamondoids are mainly sourced from the thermal cracking of oil during the late catagenesis to metagenesis， followed by kerogen maturation during catagenesis. Considering the diamondoid decomposition for the first time， we propose an evolution model of diamondoids during hydrocarbon generation in actual reservoirs， which is much more significant in revealing the primary sources and secondary processes (e.g.， evaporation fractionation) of ultra-deep hydrocarbons. In addition， this model enables us to determine the baseline and predict the ‘dead line’ for preserving liquid hydrocarbons in ultra-deep reservoirs. However， the transformation mechanisms between diamondoids and other molecular markers in deep basins need to be further investigated.

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