煤表面对多种气体分子混合吸附的微观机理  

Microcosmic mechanism of coal surface to multiple gas molecules mixed adsorption

作　　者：王继仁[1] 赵庆福[1] 邓存宝[1] 邓汉忠[1] 孙艳秋[1] 

机构地区：[1]辽宁工程技术大学安全科学与工程学院,辽宁阜新123000

出　　处：《计算机与应用化学》2008年第4期390-394,共5页Computers and Applied Chemistry

基　　金：国家自然基金(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,在6-311 g水平上对建立的吸附模型进行全优化。结果表明,煤的表面能够与多组分气体发生混合吸附。煤表面吸附氧、氮和二氧化碳分子组成的吸附态中,氧分子和氮分子在煤表面的侧链吸附,CO_2则在苯环的上方。煤表面氨基上的C原子和N原子的电子向氧分子中的氧原子转移。煤表面吸附了二氧化碳和氮分子,氧分子所得的电子减少,表明如果煤表面吸附其它种类分子,则削弱了吸附氧的作用。吸附后O_2的频率变化较大,N_2和CO_2的频率变化很小。煤表面与矿井采空区各种气体发生吸附时的亲和顺序为:氧气>水>二氧化碳>氮气>一氧化碳>甲烷。Applied quantum chemistry density functional theory, it had carried on the entire optimization to the establishment adsorp- tion model at the 6-311g level. The results show that the coal surface can have mixed adsorption with the multi-component gas. In the adsorption state of coal surface having adsorption with oxygen molecule, nitrogen molecule and carbon dioxide molecule, oxygen molecule and nitrogen molecule are absorbed in the coal surface side chain, and the CO2 is absorbed above the benzene ring. The electronics of the C atom and the N atom on the coal surface amino transfer to oxygen atom in the oxygen molecule. Carbon dioxide and nitrogen molecule are absorbed in the coal surface, and the oxygen molecule gains fewer electronics. It shows that the effect of adsorption oxygen is weakened when the other kinds of molecules are absorbed in the coal surface. After adsorption, the frequency of 02 changes greatly, but the frequency of N2 and CO2 changes very small. The affinity order is 02 〉 H20 〉 CO2 〉 N2 〉 CO 〉 CH4 , when the coal surface having adsorption with all kinds of gas in the mine goaf.

关 键 词：煤炭自燃 混合吸附 密度泛函 吸附竞争性 

分 类 号：O6[理学—化学]