噻吩与过渡金属M = (Co, Ni, Cu, Zn)吸附行为的量化研究

Abstract

如何实现过渡金属高效催化噻吩裂解脱硫是石油加工环节的重大难题。在已有的实验基础上，我们利用Gaussian03程序，采用密度泛函理论(DFT)，使用B3LYP方法在Genecp基组水平上研究了噻吩分子与四种过渡金属M = (Co, Ni, Cu, Zn)的吸附微观行为。计算结果表明：不同的过渡金属原子对噻吩分子的吸附存在着不同的吸附位，过渡金属Co与Cu吸附以α位为主，吸附后能量分别降低了479.621 kJ/mol和369.203 kJ/mol；过渡金属Ni吸附以β位为主，吸附后能量降低了高达671.241 kJ/mol；过渡金属Zn吸附以δ位为主，吸附后能量降低了165.094 kJ/mol，过渡金属Cu与Zn原子吸附噻吩分子还存在有θ位的吸附。吸附能量的计算应考虑零点能的校正。 How to realize high catalytic desulfurization of thiophene cracking of transition metals is the major problem of petroleum processing. On the basis of the existing experiment, we combine Gaussian03 progress with the density functional theory (DFT) and B3LYP method to study the thiophene molecular adsorb microscopic behavior on the four kinds of transition metal as M = (Co,Ni,Cu,Zn) on Genecp basis set level. Calculation results show that: different transition metal atoms of thiophene molecular adsorption, adsorption exists different; transition metal Co and Cu adsorption is given priority to with alpha, the energy of which after the adsorption decreased 479.621 and 369.203 kJ/mol respectively; transition metal Ni adsorption is given priority to with beta, the energy of which after the adsorption decreased as high as 671.241 kJ/mol; transition metal zinc adsorption to the delta is given priority to, the energy of which after the adsorption decreased after 165.094 kJ/mol; There is another adsorb behavior as θ position exists about thiophene molecule on the transition metal Cu and Zn. The calculation of adsorption energy should consider the zero-point energy correction.