Highly dispersed gallium-based catalysts for the non-oxidative dehydrogenation of methanol to formaldehyde and hydrogen

甲醛是最重要的工业化学品之一，主要用于生产树脂或用作合成其他化合物的积木。甲醇直接脱氢反应是一种非常有价值的反应，因为它可以得到无水甲醛和氢气。尽管氧化镓催化剂在甲醇脱氢活性和选择性方面表现出了良好的初始性能，但它们的失活率也相对较高。这是一个众所周知的问题，在脱氢催化剂上经常遇到，例如用于丙烷脱氢。这些催化剂的失活通常是由于结焦和结构变化。这些有害过程的消除将提供一种很有前途的新型镓基催化剂。由于它们在甲醇脱氢反应中的应用是相当新的，它们与该反应有关的性质将通过体感和表面敏感方法的综合组合来彻底研究。提出了一种既针对活性中心的表征又针对失活问题的研究策略。系统的催化剂设计将被用来获得高效促进的GaOx/SiO_2和CuxGayOz催化剂，并将进行瞬时动力学研究以提高其再生性。

Formaldehyde is one of the most important industrial chemicals which is mainly used for the production of resins or as a building block for the synthesis of other chemical compounds. The direct dehydrogenation of methanol is of great interest, because it results in water-free formaldehyde and hydrogen as a second valuable product. Although gallium oxide-based catalysts have been shown to display an excellent initial performance for methanol dehydrogenation in terms of activity and selectivity, their deactivation rate is also relatively high. This is a well-known problem which is encountered frequently with dehydrogenation catalysts, e. g. for propane dehydrogenation. Deactivation of these catalysts is typically due to coking and structural changes. The elimination of these detrimental processes would provide a new type of promising Ga-based catalysts. Since their application in methanol dehydrogenation is rather new, their properties with respect to this reaction will be thoroughly investigated by a comprehensive combination of bulk- and surface-sensitive methods. A research strategy is proposed that aims both at the characterization of the active sites and at tackling the deactivation problems. A systematic catalyst design will be applied to obtain efficiently promoted GaOx/SiO2 and CuxGayOz catalysts, and transient kinetic investigations will be performed to improve their regeneration.