Simulation of VOCs oxidation in a catalytic nanolith

Porous anodized aluminum oxide (AAO) structure consists of an assembly of identical pores having nanometer dimensions that span a flow reactor so as to produce an array of nano reactors, named as a catalytic nanolith. In order to understand the applicability of the nanolith in volatile organic compounds (VOCs) catalytic combustion and correlate the catalytic performance of the nanolith with its structure, a theoretical analysis of an AAO nanolith reactor dispersed with Pt for the catalytic combustion of selected VOCs (a mixture of naphthalene, propylene, propane and methane) is reported. A one-dimensional adiabatic reactor model has been developed, in which a mixed flow model considering the effect of component diffusion inside the nanopores was adopted, and the pressure drop across the nanolith nanopores as well as the exothermic nature of VOCs combustion were considered. The influence of the operational and design parameters, such as inlet temperature, pressure, and the balance gas as well as the Pt loading density, pore size and wall thickness, on the nanolith performance were studied. The results show that the pressure drop and component diffusion contributions play important roles in the performance of the nanolith reactor. These two factors also relate to the nanolith reactor design parameters, such as pore size, wall thickness and Pt dispersion etc. Considering that all these parameters plus its reactivity can all be readily tailored, the AAO nanolith reactor offers the potential for applications in VOCs catalytic combustion.