(641b) Cyclodextrins As Mass Transfer Agents for Au-Pd Nanoparticle Catalyzed Selective Oxidation Reaction of Methane in a Microfluidic Flow System

Transforming methane into methanol via direct oxidation remains to date an important challenge in the field of catalysis. The conversion has proven possible¹, yet, to successfully do so in a selective, direct, economically attractive and less energy intense fashion remains an important research goal². Recent developments show that Au-Pd nanoparticles can catalyze the oxidation of methane at mild temperatures with the use of H₂O₂, an environmentally benign oxidant, as an activator^3–5. Presently, the process has a higher yield than preceding variations but is still overall insufficient to be industrially applicable. It can be hypothesized that mass transfer limitations are a key contributor to low yields. If addressed, this process may provide the basis for a technology which can overcome the aforementioned challenges.

In the present research, the translation of this process from a traditional batch reactor used in previous research into a continuous microfluidic flow system and its feasibility was investigated. The microfluidic flow system was designed for continuous high pressure multiphase segmented flow in order to facilitate mass transfer processes via high interfacial surface to volume ratio and Taylor mixing. An additional advantage of such a system is that microreactors can expedite kinetic information compared to traditional batch reactors. The use of cyclodextrin as a mass transfer agent for the reaction was also investigated. Cyclodextrins are cyclic oligosaccharides with an internal hydrophobic cavity and external hydrophilic rim⁶. This property may be exploited to increase the solubility of methane in water and influence the final yield of the reaction. The results of these investigations will be presented and discussed.

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