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The anaerobic fluidized bed microbial fuel cell (AFBMFC) was developed to generate electricity while simultaneously treating wastewater. During a complete cycle, the AFBMFC continuously generated electricity with a maximum power density of 1100 mW/m 2 and removal of total chemical oxygen demand (COD) of 89%. To achieve this power density, the artificial electronmediator neutral red (NR) was employed in the anode chamber. Granular biological electrodes, fluidization behavior, electron mediators, and temperature were evaluated to improve power production and wastewater treatment efficiency. The results showed that the maximum power density production of granule-graphite AFBMFC was 530 mW/m 2 , much higher than 410 mW/m 2 using a granular activated carbon AFBMFC in the same reactor. Fluidization behaviors enhance the mass transfer and momentum transfer between activated carbon and wastewater. The power density increased with increasing methylene blue (MB) and NR concentration. Furthermore, power density reveals a slight increase as MB and NR concentrations exceed 0.5 and 1.7 mmol/L. The optimum temperature ranges from 23 to 40 °C. The Coulombic efficiency was 9.3% under the best operating conditions.

The adsorption and photocatalytic degradation kinetics of gaseous cyclohexane using nano-titania agglomerates were investigated in an annular fluidized bed photocatalytic reactor (AFBPR). A series of adsorption and photocatalytic degradation kinetic equations were developed to explore the relationship of adsorption/degradation efficiency and operating variables based on Langmuir adsorption law and photocatalytic elementary reactions. The adsorption equilibrium constant, adsorption active sites, and apparent reaction rate coefficient of cyclohexane were determined by linear regression analysis with variation of gas velocity and relative humidity (RH). It has been demonstrated that the initial concentration, RH, and gas velocity have obviously influenced the adsorption/photocatalytic degradation efficiency and corresponding kinetic parameters. In the adsorption process, the variation of adsorption sites and adsorption efficiency with gas velocity indicated that the adsorption controlling step was related to gas velocity. In the photocatalytic degradation process, the relationship of photocatalytic degradation efficiency and RH indicates that the water molecule played a promotion role in photocatalytic degradation of cyclohexane below a humidity inflection point, while it played an inhibition role in photocatalytic degradation of cyclohexane after this point. In addition, the optimal operating conditions were determined according to the maximum degradation efficiency with respect to RH at 20% and the fluidization number at 1.62.

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