(95e) Production of H2O2 by Controlled H2/O2 Reaction in a Microchannel Reactor

Hydrogen peroxide was formed in a microreactor in a three-phase process involving the direct combination (DC) of hydrogen and oxygen over a solid catalyst in the presence of a liquid solvent. Hydrogen and air were combined in all proportions, including explosive regime, over an in-house formulated platinum group catalyst supported on an oxide. In addition to packing the microchannel with the catalyst in particulate form, we developed closed-channel flow coating, open-channel surface-selective and dip coating methods to deposit sol-gel-based thin-film catalysts into microchannels, and cellular structures. H₂O₂ has been produced in concentrations of significant commercial interest at moderate pressure and temperature conditions and a residence time that is almost two orders of magnitude less than that for macroreactors. The multiple reactions involved in the DC process have been identified, and the reaction mechanisms elucidated with the goal of determining the overall kinetics of the hydrogen peroxide formation. Based on the extensive data acquired from the laboratory studies, an optimized process analysis, design and simulation was developed for a pilot-plant suitable for on-site production of H₂O₂ at production rates of commercial interest. The pilot-plant including the multichannel, multilayer reactor system for the demonstration of the feasibility of on-site DC process for H₂O₂ was constructed, and preliminary data obtained. This presentation will discuss the accomplishments as well as the challenges of the project.