Density Functional Theory Study on Structure of Molybdenum Carbide and Catalytic Mechanism for Methane Activation over ZSM-5 Zeolite

	Density Functional Theory Study on Structure of Molybdenum Carbide and Catalytic Mechanism for Methane Activation over ZSM-5 Zeolite
	Xing Shuangying 1; Zhou Danhong 1; Cao Liang 1; Li Xin 2
刊名	chinese journal of catalysis
	2010-04-01
卷号	31 期号:4 页码:415-422
关键词	density functional theory molybdenum carbide ZSM-5 zeolite methane activation energy
英文摘要	density functional theory (dot) calculation was employed to investigate the geometric and electronic structure of molybdenum carbide loaded on zsm-5 zeolite and the catalytic mechanism for methane c-h bond dissociation. four active center models of the monomer and dimer models were proposed, which were mo(ch2)(2)/zsm-5, mo(ch2)(2)ch3/zsm-5, mo-2(ch2)(4)/zsm-5. and mo-2(ch2)(5)/zsm-5. the monomer model was located at the bronsted acid site of the t6 site positioned at the intersection of the channels of zsm-5 zeolite. the (timer model was constructed at the t6-t6 bronsted acid sites. mo-carbene, in the form of mo=ch2, was formed in both the monomer and (timer models, and the optimized bond length of mo-c was in reasonably good agreement with the corresponding experimental value. the frontier molecular orbitals in the active center were assigned to the pi orbitals of the mo=ch2 bonds in all four models, the catalytic activity of the mo carbide active centers was investigated. it was found that the c-h bond of methane was heterogeneously dissociated with the and the h3c- moiety bonded on the c and mo atoms of the mo=ch2 bond, respectively, and the pi bond was broken simultaneously. the calculated activation energy of the methane c-h bond in the four models was between 106 and 196 kj/mol. the mo-2(ch2)(5)/zsm-5 model showed the highest activity for methane c-h bond dissociation.
WOS标题词	science & technology ; physical sciences ; technology
类目[WOS]	chemistry, applied ; chemistry, physical ; engineering, chemical
研究领域[WOS]	chemistry ; engineering
关键词[WOS]	bronsted acid sites ; mo-based catalysts ; dehydro-aromatization ; mo/hzsm-5 catalysts ; hzsm-5 zeolite ; nonoxidative conditions ; active-center ; mas nmr ; conversion ; benzene
收录类别	SCI
语种	英语
WOS记录号	WOS:000278046900010
公开日期	2015-11-17
内容类型	期刊论文
源URL	[http://159.226.238.44/handle/321008/142001]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
作者单位	1.Liaoning Normal Univ, Coll Chem & Chem Engn, Inst Chem Functionalized Mat, Dalian 116029, Liaoning, Peoples R China 2.Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, Dalian 116023, Peoples R China
推荐引用方式 GB/T 7714	Xing Shuangying,Zhou Danhong,Cao Liang,et al. Density Functional Theory Study on Structure of Molybdenum Carbide and Catalytic Mechanism for Methane Activation over ZSM-5 Zeolite[J]. chinese journal of catalysis,2010,31(4):415-422.
APA	Xing Shuangying,Zhou Danhong,Cao Liang,&Li Xin.(2010).Density Functional Theory Study on Structure of Molybdenum Carbide and Catalytic Mechanism for Methane Activation over ZSM-5 Zeolite.chinese journal of catalysis,31(4),415-422.
MLA	Xing Shuangying,et al."Density Functional Theory Study on Structure of Molybdenum Carbide and Catalytic Mechanism for Methane Activation over ZSM-5 Zeolite".chinese journal of catalysis 31.4(2010):415-422.