煤表面含P侧链基团对氧分子的物理吸附机理  

COAL SURFACE CONTAINING PHOSPHORUS GROUP PHYSICAL ADSORPTION TO OXYGEN MOLECULES MECHANISM

作　　者：邓存宝[1] 邓汉忠[1] 王继仁[1] 洪林[1] 

机构地区：[1]辽宁工程技术大学,辽宁阜新博士副教授123000

出　　处：《煤炭转化》2008年第1期1-5,共5页Coal Conversion

基　　金：国家自然科学基金资助项目(50474010);国家"十一五"科技攻关项目(2006BAK03B05)

摘　　要：应用量子化学密度泛函理论研究了煤表面带有含磷基团侧链与多氧分子物理吸附机理.煤表面中的含P基团与氧分子进行吸附组成的吸附态中,含P侧链中的P37原子和C14的电子向氧分子中的氧原子转移,P原子和C原子失去的电子主要被吸附在煤表面的氧得到,其中O23和O24得到较多电子,其他的氧原子得到的电子较少.由于吸附在煤表面上的氧分子都得到了电子,导致氧分子的O—O键被削弱,键长出现了不同程度的拉长.与自由氧分子相比,吸附在煤表面的氧分子O—O键的伸缩振动频率向低波数位移.计算得到氧分子与煤表面组成的吸附态的吸附能为606.09 kJ/mol,由此可知,煤表面含P侧链易与多个氧分子发生物理吸附.The density functional theory was used to study the physical adsorption mechanism that the coal surface side chain containing phosphorus group adsorbed many oxygen molecules. In the coal surface, the group containing phosphorus has formed the adsorption state after adsorbing many oxygen molecules. In this adsorption state, the electron of P37 atom and C14 atom moved to the oxygen molecules. The lost electron from P37 atom and C14 atom chiefly moved to the adsorbed oxygen molecules. O23 atom and O24 atom gain more electrons~ moreover other oxygen atoms gain fewer electrons. For as much as the adsorption oxygen molecules acquired the electron, the O--O bond is impaired and the bond length is draw out to a certain extent. Comparing with the free oxygen molecules, the vibrational frequency of the O--O bonds adsorbed by coal surface moved to low wave number. The energy of adsorption is 606. 09 kJ/mol, it follows that the coal surface with containing phosphorus side chain is easy adsorbing oxygen molecules, and the adsorption has physical adsorption.

关 键 词：煤炭自燃 含磷侧链基团 密度泛函 量子化学 

分 类 号：TQ531.1[化学工程—煤化学工程]