from first principles PP-I-1

PP-III-47Doped Apatite-Type Lanthanum Silicates as Catalysts forOxidative Coupling of MethaneKharlamova T.S. 1 , Matveev A.S. 1 , Sadykov V.A. 21 Tomsk State University, Tomsk, Russia2 Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russiakharlamova83@gmail.comThe oxidative coupling of methane (OCM) is an attractive method of the natural gastransformation to valuable semi-products of petrochemical synthesis, which in the measurablefuture can become competitive with the ethylene production via conventional methods [1, 2].In spite of the fact that a lot of oxide systems have been studied as catalysts for OCM, thesearch of new promising materials continues [3-5]. Recently, Zhang has shown that anapatite-type lanthanum silicate La 9.33 (SiO 4 ) 6 O 2 demonstrates a high catalytic activity in OCMat rather low temperatures [5]. In the meantime the apatite-type lanthanum silicate dopingmay provide a possibility to regulate catalytic characteristics of these materials [6, 7].In the present paper Al-doped apatite-type lanthanum silicatesLa 9.33+y/3+x (SiO 4 ) 6-у (AlO 4 ) y O 2+3x/2 , у = 0–1, x = 0,33 have been studied as catalysts for OCM.The substitution of Al for Si in the apatite structure has been shown to improve catalyticcharacteristics (C 2 -hydrocarbons selectivity and C 2 H 4 /C 2 H 6 molar retio) of lanthanum silicate.To specify the nature of such effect, the results of Raman spectroscopy, XPS as well asmethane temperature programmed reaction and isotope-exchange experiments will bediscussed.References:[1] V.S. Arutyunov, O.V. Krylov, Russian Chemical Reviews 74 (2005) 1111.[2] V.A. Menshchikov, M.Yu. Sinev, Catalysis in Industry 1 (2005) 25.[3] V.H. Rane, S.T. Chaudhari, V.R. Choudhary, Journal of Natural Gas Chemistry 19 (2010) 25.[4] T. Baidya, N. Vegten, R. Verel, Y. Jiang, et al., Journal of Catalysis 281 (2011) 241.[5] X.-H. Zhang, X. Yi, J. Zhang, Z. Xie, et al. Inorganic Chemistry 49 (2010) 10244.[6] E. Kendrick, M.S. Islam, P.R. Slater, Journal of Material Chemistry 17 (2007) 3104.200