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methane oxidative coupling ON ThO2/CaF2CATALYST

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Journal of Energy Chemistry 1995年第2期 202-211页

作者： CHAOZi-Sheng* ZHOU Xiao- PingWAN Hui-Lin TSAI Khi-RuiDepartment of Clie-mudry, Xiamen University Xiamen, Fujian 36 1 005

The oxidative coupling of methane（OCM）over ThO/CaFcatalystwas *** catalyst was found to be active and selective for *** 1153 K,the Cyield was 19.9% with 61.7% Cselectivityand 32.1% *** results indicated that F（?）Oexchangehappened between ThOand *** and Raman results suggestedthat the active oxygen species were generated and suitable for OCM reactionover the catalyst.

关键词： methane oxidative coupling catalyst ThO2/CaF2

Effect　of　Steam　on　the　oxidative　coupling　of　methane　over　La-Ba　System　Catalysts

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Chemical Research in Chinese Universities 1997年第1期13卷 41-45页

作者： PIAO Hong, BI Ying Li and ZHEN Kai ji (Department of Chemistry, Jilin University, Changchun, 130023)

The influence of steam on catalytic performance for the oxidative coupling of methane(OCM) over Ba 2+ promoted La 2 O 3 catalysts was studied. It was shown that the presence of a suitable amount of steam led to a significant increase of the yield and selectivity to C 2 hydrocarbons, a decrease of selectivity to carbon monoxide and some increase of selectivity to carbon dioxide with increasing the amount of water in the feed was also observed. The activity and selectivity of the catalysts are more sensitive to the effect of steam with the variation of Ba 2+ content in the catalysts at a relatively low temperature(650℃). The comparative experiments for OCM with methane oxygen mixture diluted with nitrogen or steam were carried out in order to investigate the role of steam.

关键词： Effect of steam methane oxidative coupling La Ba system catalysts

EHMO　Studies　of　Chemisorbed　Dioxygen　Species　on　Na＿2O　and　K＿2O　and　of　Their　Interaction　with　CH＿4　and　CH＿3－Radical

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Chemical Research in Chinese Universities 1995年第1期11卷 50-57页

作者： SU Qiao-Juan ZHANG Hong-bin ZHOU Tai-jin LIU Yu-da LIN Guo-dong and TSAI Khi-rui(Dept. of Chemistry &. State Key Laboratory for Phys. Chemistry ofthe Solid Surface , Xiarnen Univ. , Xianien , 361005) XIAMEN UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA XIAMEN UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

ith an improved EHMO method, three modes (flat-lying, vertical , and in-clined insertion) for adsorption and activation of dioxygen on (100) , (110) and(111) surfaces of Na_2O and of K,O have been exaniinecl, and the interaction ofthese dioxygen adspecies with CH_4 and with CH_3 · (radical) from gas pliase liasbeen investigated. The results indicate that both oxides tend to forni less cliargedadspecies of dioxygen, with the flat-lying adsorption on (110) surface most favor-able energetically. All these cliemisorbed dioxygen species are capable of interactingeffectively with CH_4 and Abstract ing one hydrogen atom from the CH_4 molecule andtheir tendencies to reassociate with CH_3 · , which would easily lead to deep oxida-tion of the fragments of hydrocarbons, are enhanced with inereasing negativecliarges on them. In comparison with Na_2O, K_2O has a little stronger tendency tostabilize less charged dioxygen adspecies; this has a close relation with the knownexperimental fact that K￣+ showed better promoting effect than Na￣+ in improvingC_2-selectivity in methane oxidative coupling (MOC ).

关键词： Chemisorbed dioxygen species methane oxidative coupling EHMOapproach

IN　situ　Confocal　Microprobe　Raman　Spectroscopic　Studies　on　Defective　La-based　Complex　Oxides

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Chemical Research in Chinese Universities 1997年第3期13卷 249-255页

作者： CHEN Du-hui, CAI Jun-xiu , LIAO Yuan-yian , WAN Hui-lin (Chemistry Department of Xiamen University, State Key Laboratory of Physical Chemistry for Solid Surface,Xiamen, 361005 ) XIAMEN UNIV DEPT CHEMSTATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

The adsorption of O2 over defective La2O3-based OCM catalysts with anionic vacancies , and the reaction of surface oxygen species with CH4 were studied by means of in situ confocal microprobe Raman spectra. The partially reduced oxygen species O2, O , O (Ocoupling of methane,while at higher temperature. the superoxide O2 and lattice oxygen species O2-are rather important. It is easier for fluoride-containing La2O3-based catalysts to induce the oxygen species with fewer negative charges and the basicity of the cat- alyst surface is weakened , so that the C2 selectivity for OCM reaction is improved.

关键词： methane oxidative coupling Oxygen adspecies Defective La2O3-based

Co-activation of methane and Ethane over W-Mn/SiO2 Catalyst

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分子催化 1998年第2期 6-7页

作者： ZHANG Yudong LI Shuben1) LIU Yu LIN Jingzhi(State Key Laboratory of Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsThe Chinese Academy of Sciences Lanzhou 730000)LU Guigen YANG Xuezhuang ZHANG Jing(J

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关键词： methane oxidative coupling Ethane oxidative dehydrogenation Natural gas

methane Conversion to C_2 Hydrocarbons in Solid State Oxide Electrolyte Membrane Reactor

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Journal of Donghua University(English Edition) 2005年第5期22卷 59-63页

作者：李俊赵玲朱中南奚旦立 Institute of Environment Science and Engineering Donghua University UNILAB Research Center of Chemical Reaction Engineering East China University of Science and Technology Shanghai 20023

Provskite-type catalysts, Ln0.6 Sr0.4 FexCo1-x O3 (Ln = Nd,Pr, Gd, Sm, La, 0＜x＜1) and Ln0.8Na0.2CoO3(Ln= La,Gd, Sm) were synthesized, their catalytic properties in the oxidative coupling of methane (OCM) were examined in a fixed-bed reactor. The former group presented higher activity in the OCM, but the main product was carbon dioxide. While the later group showed lower activity but much higher selectivity to C2 hydrocarbons compared with the former. Electrochemical measurements were conducted in a solid oxide membrane reactor with La0.8 Na0.2CoO3 as catalyst. The results showed that methane was oxidized to carbon dioxide and ethane by two parallel reactions. Ethane was oxidized to ethene and carbon dioxide. A fraction of ethene was oxidized deeply to carbon dioxide. The total selectivity to C2 hydrocarbons exceeded 70%. Based on the experimental results, a kinetic model was suggested to describe the reaction results.

关键词： provskiw-type catalyst methane oxidative coupling fixed-bed reactor solid oxide membrane reactor electrochemical oxygen