(493c) Design of Multichannel Photocatalytic Reactors

Photocatalysis is a promising technology to perform oxidation reactions without the use of harmful chemicals based on heavy metals. Despite the interest in the field, no practical example of a photocatalytic reactor in the industry exists. This is mainly due to the lack of synergy between photon and mass transfer in photocatalytic reactor design. A widely investigated design in the past decade is the microreactor. Despite the high volume productivity, microreactors are difficult to illuminate and are not scalable. The illumination and the scalability problem is solved by incorporating multiple microreactors in translucent structures. These structures contain multiple channels which can be coated with catalyst. The large surface area of structured reactors is easy to illuminate and allows to apply thin catalyst coatings while maintaining a sufficiently high catalyst loading.

The design flexibility of translucent structured reactors causes a more extensive design procedure than single channel reactors. The number of incorporated channels and the catalyst layer thickness are the important design parameters. Plenty of work in this field is either of experimental nature or based on numerical simulations. Researchers interested in designing their reactors to test particular catalysts or specific chemical systems want design methods or tools which can be easily used without the need for multiple experiments or complex numerical simulations. In this work, a graphical tool and an analytical design equation is proposed based on the diffusion equation in the catalyst layer. The presented procedure allows to predict the optimal catalyst layer thickness and number of structural layers based on initial calibration experiments. This reduces the number of experiments researchers have to perform to obtain an optimal design.