碱金属对煤焦异相还原NO的催化机理_量子化学研究_温正城.pdf

42 8 浙　江　大　学　学　报() Vol.42 No.8 2008 8 Journal of Zhejiang University (Engineering Science) Aug.2008 DOI:10.3785/j.issn.1008-973X.2008.08.033 NO : 温正城, 周俊虎, 王智化, 岑可法 ( , 310027) 　:NO , UB3LYP/ -31G (d) , .QCISD(T )/ -311G (d, p) , , , . , NO , , ;, NO , NO . :;;;; :TK477 　　　　　:A 　　　　　:1008-973X(2008)08-1452-0 Catalytic mechanism of alkali metal on NO heterogeneous reduction by char:quantum chemistry study WEN Zheng-cheng, ZHOU Jun-hu, WANG Zhi-hua, CEN Ke-fa (S ta te K ey L abora tory of Clean En ergy Uti liz ation, Z hej iang Un ivers ity , H angz hou 310027, Ch ina) Abstract:The reactions about the catalytic mechanism of alkali metal on NO reduction by char w ere inves- tigated by quantum chemistry.The geometry optimizations of reactants, transition states, intermediates and products of the reactions were made by using density functional theory (DFT ), UB3LYP, at -31G (d) basis function level, then the microcosmic reaction pathw ays w ere investigated.Based on the analysis of reaction pathw ays, molecule energies were calculated by a high-level ab initio method, QCISD (T )/ -311 G (d, p), and corrected with zero point energy.The activation energies w ere w orked out, and the reaction rate constants w ere calculated from transition state theory (TST ).Comparisons of the activation energies and the reaction rate constants show that the presence of alkali metal largely low ers the activation energies and quickens the reaction rate, adequately achieving the catalytic effect of NO reduction by char.With the increase of alkali metal reactivity, the reaction activation energy of alkali metal and NO decreases and the catalytic effect of NO reduction by char is strengthened. Key words:quantum chemistry;alkali