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Improving Catalytic Stability and Coke Resistance of Ni/Al_(2)O_(3) Catalysts with Ce Promoter for Relatively Low Temperature Dry Reforming of Methane Reaction

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Chemical Research in Chinese Universities 2022年第4期38卷 1032-1040页

作者： HE Lulu CHEN Xin REN Yuanhang YUE Bin TSANG Shik Chi Edman HE Heyong Department of Chemistry and Shanghai Key Laboratory of Molecular catalysis and Innovative Materials Fudan UniversityShanghai200438P.R.China wolfson catalysis Centre Department of ChemistryUniversity of OxfordOxfordOX13QRUK

A series of Ni catalysts supported on alumina with different Ce contents(1.0%–6.0%,mass fraction)was prepared by the impregnation method and used for dry reforming of methane(DRM)at a relatively low temperature of 650°C.The promotion effect of Ce with different loading amounts on the physicochemical properties of the catalysts was systematically characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),N_(2) adsorption-desorption,thermo elemental IRIS Intrepid inductively coupled plasma atomic emission spectrometer(ICP-AES),UV-visible diffuse reflectance spectroscopy(UV-Vis DRS),Fourier transformation infrared(FTIR)spectra,H_(2)-temperature programmed reduction(H_(2)-TPR)analysis,H_(2)-temperature programmed desorption(H_(2)-TPD),and The X-ray photoelectron spectroscopy(XPS)techniques.The results indicate that all the catalysts mainly exist in the NiAl_(2)O_(4) phase after being calcined at 750°C with small Ni particle sizes due to the strong metal-support interaction derived from the reduction of the NiAl_(2)O_(4) phase.The Ce-promoted catalysts show better catalytic performance as well as the resistance against sintering of Ni particles and deposition of carbon compared to the Ni/Al_(2)O_(3) catalyst.The Ni-6Ce/Al_(2)O_(3) exhibits the best catalytic stability and coke resistance among the four catalysts studied,which is due to its small Ni nanoparticles sizes,excellent reducibility as well as high amount of active oxygen species.In a 400 h stability test for DRM reaction at 650°C,Ni-6Ce/Al_(2)O_(3) exhibits less coke deposition and small growth of Ni nanoparticles.This work provides a simple way to preparing the Ni-Ce/Al_(2)O_(3) catalyst with enhanced catalytic performance in DRM.The Ni-6Ce/Al_(2)O_(3) catalyst has great potential for industrial application due to its anti-sintering ability and resistance to carbon deposition.

关键词： Dry reforming of methane(DRM) Cerium oxide Ni-based catalyst Coke resistance

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Probe-assisted NMR:Recent progress on the surface study of crystalline metal oxides with various terminated facets

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Magnetic Resonance Letters 2022年第1期2卷 9-16,I0002页

作者： Yung-Kang Peng Shik-chi Edman Tsang Department of Chemistry City University of Hong KongKowloon TongHong Kong SAR0000China The wolfson catalysis Centre Department of ChemistryUniversity of OxfordOxfordOX13QRUK

The development of metal oxides with specific facet exposure for better catalytic performance in targeted applications has been well-documented.However,the understanding of surface structure-activity correlation is severely hindered by the current poor resolution of conventional surface characterization tools.In this mini-review,some of the latest research developments on the characterization of the surface structure and properties of faceted ZnO and TiO_(2)by probe-assisted nuclear magnetic resonance spectroscopy(NMR)are discussed.

关键词： Probe-assisted nuclear magnetic resonance Surface structure-property relationship ZnO TiO_(2)

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Tungsten Promoted Ni/Al_2O_3 Catalysts for Carbon Dioxide Reforming of Methane to Synthesis Gas

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Chemical Research in Chinese Universities 2004年第4期20卷 470-477页

作者： Thomas Suhartanto Andrew P. E. York Malcolm L. H. Green wolfson catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of Oxford South Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UK

A series of tungsten promoted alumina supported nickel catalysts has been prepared for the carbon dioxide reforming of methane to synthesis gas. The catalysts have been characterized by means of XRD, TEM, and Laser Raman spectroscopy. It is shown that the addition of tungsten to the nickel catalyst can stabilize the catalyst and increase the resistance to carbon deposition. Adding a suitable amount of tungsten can also increase the catalyst activity to be close to that of supported noble metal catalysts. The carburisation of the tungsten modified nickel catalyst decreases the catalyst activity at lower reaction temperatures(<1123K), but has no effect on the catalyst performance at higher reaction temperatures. The alumina supported nickel catalyst modified by 0.67%(mass fraction) WO_3 has the equivalent equilibrium constant of the dry reforming reaction to that of alumina supported 5%(mass fraction) Ru at 873 K, and also has a lower activation energy for dry reforming than the latter.

关键词： Nickel catalyst Tungsten modifier CO_2 reforming Methane Syngas

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Preparation of MCM-41 in Industrial Scale and Its Application in Heavy Oil Processing

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Chemical Research in Chinese Universities 2002年第2期18卷 169-174页

作者： Jianwen Da Tiancun Xiao Jianming Su Xingzhong Xu Malcolm L.H.Green Research Institute of Qilu Petrochem.Corp. Zibo 255400China The wolfson catalysis Centre Inorganic Chemistry LaboratoryUniversity of OxfordSouth Parks RoadOxfordOX13QRUK

A series of MCM 41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM 41 product have been studied by using X ray diffraction(XRD), thermogravimetric(TG) and electron microscopy(TEM). It is shown that the pH values have a significant effect on the crystallinity of the synthesized product. Under proper conditions, the MCM 41 prepared on an industrial scale has the same performance as the samples prepared on an Lab scale. The prepared MCM 41 was used as a modifier of zeolite Y for fluid catalytic cracking(FCC) of residual oil. It is shown that the addition of the MCM 41 in the zeolite Y catalyst increases the pore size, and surface area of the catalysts, which helps to increase the yield of gasoline and diesel and decrease the production of gaseous product and carbon deposition in the catalyst. The better performance of the MCM 41 modified zeolite Y catalyst is believed to be due to its adjustment on the acidity and increase of the pore size.

关键词： MCM-41 Industrial scale synthesis FCC catalyst

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Effect of Bronsted/Lewis Acid Ratio on Conversion of Sugars to 5-Hydroxymethylfurfural over Mesoporous Nb and Nb-W Oxides

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Chinese Journal of Chemistry 2017年第10期35卷 1529-1539页

作者： Bin Guo Lin Ye Gangfeng Tang Li Zhang Bin Yue Shik Chi Edman Tsang Heyong He Department of Chemistry and Shanghai Key Laboratory of Molecular catalysis and Innovative Materials Col- laborative Innovation Center of Chemistry for Energy Materials Fudan University Shanghai 200433 China wolfson catalysis Centre Department of Chemistry University of Oxford Oxford OX1 3QR UK

A series of mesoporous Nb and Nb-W oxides were employed as highly active solid acid catalysts for the con- version of glucose to 5-hydroxymethylfurfural （HMF）. The results of solid state 31p MAS NMR spectroscopy with adsorbed trimethylphosphine as probe molecule show that the addition of W in niobium oxide increases the number of Bronsted acid sites and decreases the number of Lewis acid sites. The catalytic performance for Nb-W oxides varied with the ratio of Bronsted to Lewis acid sites and high glucose conversion was observed over NbsW5 and NbTWs oxides with high ratios of Bronsted to Lewis acid sites. All Nb-W oxides show a relatively high selectivity of HMF, whereas no HMF forms over sulfuric acid due to its pure Bronsted acidity. The results indicate fast isom- erization of glucose to fructose over Lewis acid sites followed by dehydration of fructose to HMF over Bronsted acid sites. Moreover, comparing to the reaction occurred in aqueous media, the 2-butanol/H2O system enhances the HMF selectivity and stabilizes the activity of the catalysts which gives the highest HMF selectivity of 52% over NbTW3 oxide. The 2-butanol/H2O catalytic system can also be employed in conversion of sucrose, achieving HMF selectivity of 46% over Nb5W5 oxide.

关键词： carbohydrates glucose HMF Nb-W oxide heterogeneous catalysis

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Monitoring and Manipulation of Atomic Interface in catalysis

Monitoring and Manipulation of Atomic Interface in Catalysis

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中国化学会第30届学术年会-第十五分会：表界面结构调控...

作者： Shik Chi Edman Tsang The wolfson catalysis Centre Department of ChemistryUniversity of Oxford

＜正＞Recent developments in nano-science and novel analytical characterization have opened up new directions in chemistry to allow the synthesis of new catalytic materials which could not be obtained by conventional means.The current research shows that they exhibit many fascinating surface,size and shape dependent properties.The use of well-defined,

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基于化学链的氨生产--一种有前途的非碳燃料生产途径

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Science Bulletin 2022年第20期67卷 2124-2138,M0004页

作者：赖清华蔡天意 Shik Chi Edman Tsang 陈侠叶润平徐政和 Morris DArgyle 丁冬陈咏梅王键吉 Armistead GRussell 吴烨刘健范貌宏 College of Engineering and Applied Science University of WyomingLaramie WY 82071USA School of Energy and Power Engineering Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China wolfson catalysis Department of ChemistryUniversity of OxfordOxford Ox13QRUK College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Chemical and Materials Engineering University of AlbertaEdmonton Alberta T6G1H9Canada Department of Chemical Engineering Brigham Young UniversityProvo UT 84602USA Idaho National Laboratory Idaho Falls ID83415USA College of Chemistry Beijing University of Chemical TechnologyBejing 100029China School of Chemistry and Environmental Science Henan Normal UniversityXinxiang 453007China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlanta GA 30332USA MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Power EngineeringNanjing University of Science&TechnologyNanjing 210094China DICP-Surrey Joint Centre for Future Materials Department of Chemical and Process Engineeringand Advanced Technology InstituteUniversity of SurreyGuilford Surrey GU27XH UK

氨既是最基本的化工原料之一,也是一种很有前景的非碳燃料,可用于防止全球变暖.氨主要由1909年开发的曾获得两项诺贝尔奖的哈伯-博世工艺制成.然而该工艺过程有一些缺点,包括高碳足迹和需要苛刻的反应条件.有数据统计,用于全世界的合成... 详细信息

氨既是最基本的化工原料之一,也是一种很有前景的非碳燃料,可用于防止全球变暖.氨主要由1909年开发的曾获得两项诺贝尔奖的哈伯-博世工艺制成.然而该工艺过程有一些缺点,包括高碳足迹和需要苛刻的反应条件.有数据统计,用于全世界的合成氨上的能源占全球天然气产量的3%~5%和全球能源消耗的1%~2%.这使得开发替代的合成氨的方法很有必要.基于化学链的氨生产使用氮载体材料,可以在大气压下运行并实现高产品选择性和高能源效率.迄今为止,在这个关键领域还缺乏关于氮载体和基于化学链的氨生产系统的综述和展望.本文旨在全面回顾化学链的氨生产的最新进展,并总结性地展望了化学链的氨生产的未来发展.本文首先讨论了可持续的、基于化学链的氨生产的途径和氨的利用;然后,根据反应物和中间步骤将基于化学链的氨生产系统性地分为四类.此外,文章还全面回顾了每一类基于化学链的氨生产的氮载体的最新发展和所需的热力学性质;最后对基于化学链的氨生产技术的发展方向进行了展望.

关键词：化学链化工原料数据统计载体材料热力学性质中间步骤诺贝尔奖全球变暖

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Entrapped single tungstate site in zeolite for cooperative catalysis of olefin metathesis with Br?nsted acid site

Entrapped single tungstate site in zeolite for cooperative c...

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中国化学会第三届中国能源材料化学研讨会

作者： Pu Zhao Lin Ye Zhenyu Sun Benedict T.W.Lo Harry Woodcock Chen Huang Chiu Tang Angus I.Kirkland Donghai Mei S.C.Edman Tsang wolfson catalysis Centre Department of ChemistryUniversity of Oxford Department of Materials University of Oxford Diamond Light Source Ltd. Harwell Science and Innovation Campus Physical and Computational Sciences Directorate & Institute for Integrated catalysis Pacific Northwest National LaboratoryPO Box 999

＜正＞Industrial olefin metathesis catalysts generally suffer from low reaction rates and require harsh reaction conditions for moderate activities.This is due to their inability to prevent metathesis active sites（MASs） from aggregation and their intrinsic poor adsorption and activation of olefin molecules.Here,isolated tungstate species as single molecular MASs are immobilized inside zeolite pores by Br?nsted acid sites（BASs） on the inner surface.

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氧化钽及钽钨复合氧化物固体酸催化己糖脱水制备5-羟甲基糠醛以及非等计量比的甲酸和乙酰丙酸

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Chinese Journal of catalysis 2020年第8期41卷 1248-1260页

作者：郭斌贺露露唐钢锋张丽叶林岳斌曾适之贺鹤勇复旦大学化学系能源材料化学协同创新中心上海市分子催化与功能材料重点实验室中国上海200433 牛津大学化学系 Wolfson催化中心英国

5-羟甲基糠醛(HMF)是最具应用前景的平台化合物之一,HMF制备的研究越来越成为热点,并且已经取得了令人瞩目的研究成果.尽管如此,在现阶段利用固体酸催化剂催化碳水化合物制备HMF的研究仍然面临许多挑战,以葡萄糖为原料制备HMF时产物选... 详细信息

5-羟甲基糠醛(HMF)是最具应用前景的平台化合物之一,HMF制备的研究越来越成为热点,并且已经取得了令人瞩目的研究成果.尽管如此,在现阶段利用固体酸催化剂催化碳水化合物制备HMF的研究仍然面临许多挑战,以葡萄糖为原料制备HMF时产物选择性普遍较低.因此,合成制备高活性催化糖类化合物脱水制HMF的固体酸催化剂,并且研究固体酸催化剂表面酸性质比如酸密度、酸强度以及Bronsted/Lewis酸比值等对糖类化合物制HMF反应中各反应产物选择性的影响,对新型高效催化剂的开发设计具有重要意义.本文通过溶剂挥发自组装法合成了一系列介孔Ta及Ta-W氧化物固体酸催化剂,并用于催化果糖和葡萄糖脱水制备5-羟甲基糠醛.以三甲基膦(TMP)为探针分子,利用^31P固体核磁共振谱技术表征催化剂表面酸性质,考察复合金属氧化物固体酸催化剂酸量、酸强度以及酸类型对催化果糖和葡萄糖制备HMF反应性能的影响,为高效催化剂的设计提供一定的理论指导.另外,我们还通过引入2-丁醇构建有机溶剂/水体系,考察有机溶剂对葡萄糖脱水制HMF反应中所用催化剂活性和产物选择性的影响.31P固体核磁共振技术表征样品的酸性质发现,随着W掺杂量的增加,系列Ta及Ta-W氧化物的酸强度和Bronsted/Lewis酸量比值逐渐增加.催化反应结果表明,以介孔Ta及Ta-W复合氧化物为催化剂时,果糖和葡萄糖脱水制HMF反应的催化活性和HMF选择性与所用催化剂的酸量、酸类型和酸强度有关.介孔Ta及Ta-W复合氧化物催化剂表面的B/L比值越高,催化反应过程中的己糖转化率也越高,HMF选择性也普遍越高.具有较高Bronsted酸强度的催化剂在水溶液中更易降低HMF产物选择性,归结于HMF的再水解和葡萄糖的非选择性脱水等副反应.实验结果发现,产物甲酸(FA)的选择性远高于乙酰丙酸(LA),说明过量FA很可能来自果糖在Lewis酸位上的分解.2-丁醇的引入能够提高己糖转化率和HMF选择性,并且在B/L比值越高的催化剂上提升的效果越显著.其中,Ta7W3氧化物为催化剂时,HMF选择性最高可达54%,并且该催化剂具有良好的催化稳定性,这主要是因为2-丁醇的加入能够有效地抑制反应中胡敏素等聚合物的生成,防止后者在催化剂表面附着导致催化活性降低,进而提高了催化剂在催化反应中的稳定性.

关键词：葡萄糖果糖 5-羟甲基糠醛固体酸氧化钽 Ta-W氧化物

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