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In this study, a microbial fuel cell (MFC) with granular activated carbon packed anode (GAC-MFC) is developed and compared with a MFC with granular graphite packed anode (GG-MFC), to evaluate the adsorptive effect of the granular activated carbon anode on MFC’s performance. The current output of GAC-MFC (11.1 mA, 18.1 mA and 21.6 mA) is much higher than that of GG-MFC (4.87 mA, 12.5 mA and 17.9 mA) at low substrate COD concentrations (∼50, ∼100 and ∼200 mg/L) when a low external resistance (20 Ω) and high circulation flow rate (20 mL/min) are applied. The half-saturation constant ( K s ) of GAC-MFC is about half as much as that of GG-MFC, suggesting that GAC-MFC has more affinity for anode substrate and deliver better kinetic performance than GG-MFC. Internal resistance distribution shows that mass diffusion resistance of GAC-MFC is at least 50% lower than that of GG-MFC when the substrate COD is ∼50 mg/L, indicating that the adsorptive effect of granular activated carbon packed anode helps to effectively facilitate mass transfer at low COD concentrations. Otherwise, the substrates adsorbed on GAC surface also serve to buffer the impact of COD concentration plummeting in bulk solution. [ABSTRACT FROM AUTHOR]

• A pilot-scale bubbling fluidized bed adsorption device was designed and operated. • Bubbling fluidized bed is suitable to recovery the industrial VOCs. • Diffusion is the rate-determining factor of adsorption. • The adsorption rate of the bubbling fluidized bed is significantly high. • The optimized conditions of bed height is 40 mm for the bubbling fluidized bed. Adsorption is one of the most efficient inexpensive strategies for the removal of volatile organic compounds (VOCs). However, adsorption of VOCs by fixed beds has certain limitations, such as considerable energy consumption and high operating costs. To treat VOCs with high volume and low concentration, a pilot-scale multistage bubbling fluidized bed adsorber was developed herein and was used to conduct the adsorption experiments. Experimental investigation of ethanol adsorption on the adsorbent under static and dynamic conditions revealed that ethanol adsorption on the adsorbent followed the Langmuir adsorption model. The adsorption kinetics followed a linear driving force (LDF) model, which showed that diffusion was the rate-determining factor. Moreover, the effects of operating conditions, such as bed height, superficial gas velocity, inlet concentration, and desorption temperature, on adsorption were investigated. The results showed that adsorption efficiency in the bubbling fluidized bed varied from 85.7% to 94.5%. The findings of this study could provide the basic data for the design and development of a bubbling fluidized bed for application in the recovery of low-to-medium concentrations of industrial VOCs. [ABSTRACT FROM AUTHOR]