还原性工业烟气中硫物种与碳资源协同资源化利用的基础研究

In China, the reduction of CO2 emission is facing unprecedented pressures and changes,and the research on the coping with reduced sulfur species of industrials flue gas is relativly weaker with respect to oxided sulfur species. In the project, we are going to prepare methyl mercaptan with reduced sulfur species and carbon resources arisen from industrials flue gases, which is one of urgently needed products of domestic market.By this way, not only the influence of reduced sulfur species on environment can be effectively eliminated but these reduced sulfur species will be resourced with high value.Ordered mesoporous molecular sieves with high surface area, well-defined pore structures,tunable pore diameters and controllable acidity should be the perfect supports. The synthesis of catalysts with high-performance plays an vital role in determining the yield of co-resourcing sulfur species and carbon resources. The modulation laws of catalytic centers were investigated according to catalytic activity, physico-chemical properties, microstructure characterization and catalytic dynamics, and the interrelationship between catalytic activity and the corresponding structure was explored. In light of these researches, the catalytic and deactivation mechanisms will be investigated and revealed in detail. Implementation of this project,the achievements not only would be in favor of the reduction of CO2 and SO2 in China but provide a theoretical basis for the synthesis of methl mercaptan.

我国CO2减排遇到前所未有的压力与挑战，且对还原性工业烟气中硫物种的处理相对薄弱。本项目提出以还原性气体中的硫物种与碳资源为原料，通过研制高性能催化剂将其转化为国内市场急需的化工产品- - 甲硫醇。不仅可消除还原性硫物种对环境的影响并实现其高值资源化，而且可获得市场急需化工产品和有利于CO2减排。介孔分子筛具有高的比表面、孔径均一且可调好、表面酸碱性可控等有点，是甲硫醇合成的理想催化剂载体。研制高性能的催化剂是实现碳与硫物种高效协同资源化利用的关键。本研究在催化剂活性评价、动力学研究、物化性能与微观结构的基础上，探索催化剂活性中心的调变规律，构建碳与硫物共资源化催化剂结构与活性之间的构效关系，揭示硫物种与碳资源协同资源化的反应机理与催化剂的失活机制。项目研究成果可为我国CO2与SO2减排以及甲硫醇的合成提供可靠的理论依据。

本项目以还原性工业烟气中硫物种与碳资源协同资源化合成我国市场急需的甲硫醇为研究目标，以合成高水热稳定性SBA-15介孔分子筛为载体，通过制备方法和活性组分的筛选与优化，研制了系列高性能的Mo基催化剂。对实际催化反应条件进行了全面的研究，确定最佳反应温度，空速，压力以确保最高的碳物种和硫物种转化率以及甲硫醇选择性。利用氮气吸脱附、UV-vis、XRD、H2-TPR、H2S-TPS、TEM和XPS等表征对催化剂的微观结构及活性中心调变规律进行探究，并借助于热力学、动力学、中间产物加氢研究以及理论计算取得如下主要结论：COS是合成甲硫醇的重要中间产物，但目前文献报道CO/H2S/H2反应体系合成甲硫醇的机理为COS先歧化生成CS2，CS2进一步加氢合成甲硫醇。本项目通过热力学、动力学以及理论计算证实了COS可直接加氢合成甲硫醇；通过调控催化剂的合成条件与参数，探究了MoS2、K插入型MoS2和K修饰型MoS2等三种活性相的转化过程以及他们在甲硫醇合成过程中的不同作用机理；通过反应条件的优化、中间产物（COS和CS2）的加氢研究及理论计算，提出了CO/H2S/H2反应体系合成甲硫醇的反应路径。项目研究成果不仅可为还原性烟气中碳、硫物种的协同高值资源化利用提供了重要的实验数据和理论基础，而且为甲硫醇工业化生产提供技术支撑。已发表学术论文14篇，其中SCI、EI收录12篇；申请发明专利3项。培养研究生6名。