In this research, the utilization of an algal assisted-microbial fuel cell (AMFC) that employed photosynthetic microorganisms as cathode catalysts was demonstrated for the treatment of synthetic wastewater (SWW), power generation, and carbon sequestration. The power and biomass generation of two photosynthetic microorganisms, namely Chlorella sorokiniana and Tetradesmus sp., were evaluated. The electrogenic activity of Citrobacter frundii present in the SWW was analyzed using cyclic and linear sweep voltammetry. The AMFC exhibited a higher power density of 47.57 ± 0.95 mW/m3 with Chlorella sorokiniana in comparison to Tetradesmus sp. (46.56 ± 0.95 mW/m3). Additionally, the effect of CO2 supply on AMFC performance was investigated. The simultaneous treatment and energy recovery from low-grade waste such as SWW was found to be feasible with COD removal efficiency of 74 ± 0.6% in both AMFCs. Furthermore, the elementary analysis of lyophilized biomass of Chlorella sorokiniana and Tetradesmus sp in SWW-B showed maximum carbon content of 49.3% and 49.1%, respectively. The maximum biomass concentration and carbon fixation rate were determined to be 2.8 ± 0.03 g L−1 d−1 and 1.4 ± 0.001 g L−1 d−1, respectively for Chlorella sorokiniana. Additionally, the series of experimental results show that the stacked AMFCs had the capability to light the 3.0 V LED bulb. These findings suggest that AMFCs have the potential for sustainable bioelectricity generation and wastewater treatment with added benefits of carbon sequestration and biomass production.
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