Catalytic Synthesis of Hydrogen Peroxide in a Capillary Microreactor

The direct synthesis of hydrogen peroxide from hydrogen and oxygen has been investigated in a capillary and a stacked microreactor, where Pd/C catalyst was coated on the silicone wall of a microchannel. In order to make the system of H2O2 production compact, a flow-through solid polymer electrolyte (SPE) electrolyzer, which was used for the evolution of H2 and O2 instead of gas cylinders, was connected to the microreactor. The influences of gas and liquid flow rates and reaction temperature on the H2O2 production were investigated to obtain the optimum operation conditions of the stacked microreactor. As a result, a H2O2 concentration of 8.3 x 10 mol/L was obtained at 10C in 0.1 mol/L HCl solution in the short-contacttime microreactor. In addition, H2O2 was successfully produced by flowing pure water with H2 and O2 in the stacked microreactor.