A steady-state ID macro-homogeneous model is developed to illustrate the combustion process of methane with ozone in the reactor composed of Pd-exchanged zeolite X. The model is validated by comparing the predicted results with the measured data. The methane conversion increases with decreasing the inlet methane concentration and gas space velocity and increasing the inlet ozone concentration and temperature. As the reactor length reduces, the methane conversion varies little if the reactor is too long but decreases when the reactor is too short. Therefore, the reactor should he properly designed to balance costs and the methane-conversion efficiency.
In this study, a membraneless, monolithic micro photocatalytic fuel cell with an air-breathing cathode was developed for simultaneous wastewater treatment and electricity generation. In this newly-developed micro photocatalytic fuel cell, the photoanode and cathode were arranged with a shoulder-to-shoulder design, forming two planar electrodes. Such design offers several advantages of enhanced mass transfer, uniform light distribution, short light transfer path, membrane elimination and easy fabrication, integration, and compatibility with other microdevices. The performance of this type fuel cell was evaluated by using methanol as a model pollutant under the alkaline condition. Experimental results indicated the developed micro photocatalytic fuel cell was able to show good photo-response to the illumination and satisfactory performance as well as durability. Parametric study on the cell performance was also performed. It was found that increasing the light intensity, methanol concentration andKOH concentration could improve the cell performance. But for the effect of the liquid flow rate, it was shown that the cell performance firstly increased with increasing the liquid flow rate and then decreased with further increasing the liquid flow rate. This study not only opens a new avenue for the design of the micro photocatalytic fuel cell but also is helpful for the optimization of the operating conditions.
Ming XiaRong ChenXun ZhuQiang LiaoLiang AnZhibin WangXuefeng HeLong Jiao
