甲醇在过渡金属上反应机理的BOC-MP法研究  

BOC-MP Study on the Mechanism of Reactions of Methanol on Transition Metals

作　　者：黑美军[1] 陈鸿博[1] 林贻基 洪琦[1] 林银钟[1] 易军[1] 廖代伟[1] 蔡启瑞[1] 

机构地区：[1]厦门大学物理化学研究所

出　　处：《Chinese Journal of Chemical Physics》1998年第2期166-173,共8页化学物理学报（英文）

基　　金：国家自然科学基金;国家教委留学回国人员科研资助

摘　　要：运用键级守恒莫尔势函数法（ＢＯＣ－ＭＰ）对ＣＨ３ＯＨ在过渡金属Ａｇ（１１０）、Ｃｕ（１１１）、Ｐｄ（１１１）、Ｎｉ（１１１）、Ｐｔ（１１１）面上的解离和临氧条件正气反应机理进行了探讨。结果表明ＣＨ３ＯＨ在清洁过渡金属表面可能发生Ｃ－Ｏ键或Ｃ－Ｈ键的断裂，生成ＣＨｘ（ｘ＝２，３）物种。在临氧条件下，ＣＨ３ＯＨ直接氧化生成ＨＣＯＨ。The mechanism of dissociation of methanol and its reactions with oxygen on transition metal surfaces,Ag(111),Cu(111),Pd(111),Ni(111)and Pt(111),are analyzed by the Bond-Order-Conservation-Morse-Potential(BOC-MP)approach.It is shown that the cleavage of the C-O bond or C-H bond of methanol may takes place,resulting the formation of the CH x(x=2,3)species.However,in the presence of oxygen,the methanol is directly oxidized to formaldehyde. The calculation values of activation barrier by BOC-MP approach are in good agreement with the experimental values.The results showed that the HCOH is very easy oxidized into CO or CO_2 on the surface of Ni,Pd,Pt,Cu and Ag.So,the very small amount of oxygen must be controlled for the system oxidizing mathanol to formaldehyde by transition metal catalysts. The easy order is Ni>Pd>Pt>Cu>Ag for dissociation of mathanol over transition metal catalysts.However,in very low oxygen content,the carbon deposition is more easy on Ni,Pd and Pt than Cu adn Ag surface.Therfore,The Cu and Ag rather than Ni,Pd and Pt are used in the commercial catalysts for the oxidation of mathanol to formaldehyde.

关 键 词：键级守恒 甲醇 分解 氧化 甲醛 催化剂 合成 

分 类 号：O623.511[理学—有机化学]