Many kinds of substrates have been used to investigate bioelectricity production with Microbial Fuel Cell (MFC). Dry algae biomass has the highest maximum power density compared to other substrates due to high carbon sources from its lipid. However, the bacterial digestion of algae biomass is not simple because of the complexity and strength of the algal cell wall structure. An algae biomass extraction is needed to break the cell wall structure and facilitate digestion. Spray drying method is commonly used in highvalue products but may degrade some algal components which are crucial for microbial degradation in MFC, while the freeze-drying method is able to preserve algal cell constituents. The MFC was fed with freeze dried and spray dried algae biomass to produce energy and determine the degradation efficiency. Results showed the average voltage generated was 739 mV and 740 mV from freeze dried and spray dried algae biomass, respectively. The maximum power density of freeze dried algae biomass is 159.9 mW/m2 and spray dried algae biomass is 152.3 mW/m2. Freeze dried algae biomass has 54.2% of COD removal and 28.4% of Coulombic Efficiency while spray dried algae biomass has 50.1% of COD removal and 24.9% of Coulombic Efficiency.
io-electricity generation by Microbial Fuel Cell (MFC) has gained considerable attention due to
its integration with wastewater treatment such as Palm Oil Mill Effluent (POME). Investigation
into pH effect and determination of optimal pH value ranges growth for acidogenic, acetogenic
and methanogenic by natural mixed culture
electroactive bacteria (exoelectrogens) growth
in original non-Deoxygenated Mixed POME
(nDMP) and Deoxygenated Mixed POME (DMP)
in MFC was carried out. Current generation,
power generation and maximum power were
also monitored. Experimental results show that
exoelectrogens in nDMP with pH 6.8 yielded the
highest current generation of 61.51 mAm-2 and
maximum power of 17.63 mWm-2. Overall, nDMP
substrates with 3 pH ranges (5.5, 6.8 and 8.0)
showed equal potential to generate power that is
higher than DMP substrates. Comparison carried
out for inter DMP substrates demonstrated that
DMP with pH 6.8 and DMP with pH 8.0 showed equal potential to generate power, but not for DMP with pH 5.5. Subsequently, nDMP with pH 6.8 and
nDMP with pH 8.0 showed equal potential for higher maximum power compared to nDMP with pH
5.5 and DMP substrates. This finding indicates that mixed microbial communities in DMP substrate
are dominant with obligate anaerobic exoelectrogens bacteria which have less capability to generate
electricity compared to nDMP substrate that was dominated by the aerotolerant and/or facultative
anaerobic exoelectrogens bacteria.