With a rapid developing global economy and population growth, demand for natural gas is expected to outpace supply. Current state of the art methanation catalysts like nickel-based (Ni) catalysts are susceptible to poisoning by sulfuric compounds present in the syngas. MoS₂ is one of the few methanation catalysts not affected by sulfuric impurities, allowing the use of syngas feedstocks from coal gasification for direct methanation before extensive clean-up of the syngas. Increasing the number of Mo active sites is challenging since they are mostly located at the edges while the basal planes are mostly inert. In this study, we report a method of producing MoS₂ with a significant amount of exposed edges (nano-flakes) which resulted in highly active MoS₂ catalysts. Effects of support, Mo precursors and synthesis techniques on the formation of nano-MoS₂ structure and methanation activity have been investigated. MoS₂ nano-flakes can be produced from a solvothermal method or thermolysis of a thiomolydate precursor. The resulting MoS₂ catalysts were tested for direct methanation of CO with H₂ to CO ratio of 1:1 and 3000 ppm of H₂S under 3 MPa. X-ray absorption spectroscopy was also utilized to gain more insight into the structure of the catalysts.

随着全球经济的快速发展和人口的增长，对天然气的需求有望超过供应。当前的最先进的甲烷化催化剂，例如镍基（Ni）催化剂易受合成气中存在的硫化合物中毒的影响。MoS ₂是少数不受硫杂质影响的甲烷化催化剂之一，可在进一步净化合成气之前，使用煤气化制得的合成气原料进行直接甲烷化。增加Mo活性位点的数量具有挑战性，因为它们主要位于边缘，而基面通常是惰性的。在这项研究中，我们报告了一种生产MoS ₂的方法，该方法具有大量的裸露边缘（纳米薄片），从而导致高活性的MoS ₂催化剂。研究了载体，Mo前驱体和合成技术对纳米MoS ₂结构的形成和甲烷化活性的影响。MoS ₂纳米薄片可以通过溶剂热法或硫代钼酸盐前体的热解制备。测试了所得的MoS ₂催化剂在3 MPa下H ₂与CO的比例为1：1的CO和3000 ppm的H ₂ S的直接甲烷化。X射线吸收光谱法还用于获得对催化剂结构的更多了解。