噻吩类含硫模型化合物的降解机理研究

The investigation on the degradation mechanism of the thiophene sulfur model compound

为了探究煤中噻吩类有机硫化合物降解规律,采用密度泛函理论搜索过渡态提出了两条反应路径.通过对反应路径中各物种的原子电荷、热力学、动力学参数和噻吩降解的势能剖面图分析得出:各路径发生的难易程度是不同的,噻吩降解的最有利的反应路径为Path1,即首先是H9转移到S5上,接着H8从C3转移到C4上伴随着C4-S5键的断裂,然后H6转移到S5上,最后随着H7从C2转移到C1上,H2S离开原来的结构,丁二炔形成.利用密度泛函理论对煤中噻吩类含硫模型化合物在不同降解路径中的变化规律进行研究,可以有助于理解煤中噻吩硫的脱除机理,为煤中噻吩类有机硫的脱除实验及工业处理过程提供理论指导.

In order to explore the degradation regularity of the thiophene organic sulfur compounds in coal. Through searching transition states, it proposes two reaction paths using the density functional theory. It gets that the difficulty of each path is different, the more favourable reaction path of thiophene degradation is Path 1 basing on atomic charges of every species, thermodynamics and dynamics parameters of the reaction paths and the analyzing the potential energy profiles of thiophene degradation. Firstly, H9 transfers to S5, then H8 transfers from C3 to C4 with C4-S5 bond fracturing, H6 transfers to S5. Finally, with the H7 transfering from C2 to C1, H2S deviates from the original structure and diacetylene formats. The changing rule of the different degradation paths of the thiophene sulfur model compounds in coal were studied using the density functional theory, it can help to understand the removal mechanism of the thiophenic sulfur in coal and provide theoretical guidance for experiments of the thiophene organic sulfur removal in coal and industrial process.