基质隔离条件下金属氢化物催化H2S绿色转化的实验与理论研究

At present, H2S is primarily treated with Claus process wherein it is partially oxidized to yield elemental S and water. Although S can be extracted from H2S with this approach, one of the disadvantages is the loss of H2 in H2S during the conversion. Therefore, it is highly desirable to develop a sustainable and cost-effective process to simultaneously recover H2 and S from H2S. The project will study the reactions of TiH2 with hydrogen sulfide using a combined method of matrix isolation infrared spectra spectroscopy and quantum chemical theoretical calculation. The product absorption variation upon concentrations, annealing, and photolysis isomerization reaction will be compared with the vibrational characteristics of anticipated products calculated. New product absorptions will be assigned on the basis of frequency isotopic shifts and frequency calculations. Structural characteristics of intermediates HxTiS will be analyzed, the mechanism about the S-H bond activation of hydrogen sulfide by TiH2 will be discussed. On this basis, the reactions of metal hydride MHx (M = Zr、Hf、Cr、Mo、W、Cu、Ag、Au) with hydrogen sulfide further will be carried out in order to reveal the rule of recover H2 and S from H2S. These results will provide theoretical guidance for the novel design of dehydrogenation and desulfurization of H2S from the process of gas and petrochemicals.

目前，硫化氢主要通过克劳斯工艺进行处理，部分氧化得到水和硫，但是硫化氢中的氢却以水的形式放出，造成氢资源的浪费。因此，开发一种能够同时得到氢气和硫的可持续的低成本的过程具有非常大的研究潜力。本项目拟采用低温基质隔离红外光谱方法，通过升温退火和光诱导异构化反应，研究TiH2催化硫化氢转化分解得到氢气和硫的反应，结合量子化学理论计算和同位素取代实验，对红外吸收光谱进行归属，研究中间体HxTiS的结构特征，阐明TiH2催化H2S绿色转化的反应机理。在此基础上，将进一步研究MHx (M = Zr、Hf、Cr、Mo、W、Cu、Ag、Au)等金属氢化物与H2S的反应，从而揭示金属氢化物催化硫化氢绿色转化制氢脱硫的规律，为天然气和石油化工过程中产生的大量H2S资源高值转化（H2+S）提供潜在的新途径。

硫化氢在制备氢气和单质硫方面具有潜在的应用而备受人们的关注，寻找高效且可持续的脱硫制氢方法是研究的热点，而金属催化机理研究可以为此技术的实际应用提供理论基础。利用红外光谱、同位素取代与量子化学计算研究金属催化转化H2S的活性中间体及反应机理。具体研究内容包括：（1）基质隔离红外光谱与量子化学计算研究B、Al、Ga与H2S的反应；（2）在氩基质中Cr, Fe, Mn催化H2S转化的中间体捕获及反应机理研究；（3）Co催化剂对小分子的吸附活化及反应机理研究。本项目为天然气和石油化工过程中产生的大量H2S资源高值转化（H2+S）提供潜在的新途径。