Effects of carbon source on electricity generation and PAH removal in aquaculture sediment microbial fuel cells

Sediment microbial fuel cells (SMFCs) have been used for treating pollutants in sediment or overlying water. This study investigated the feasibility of constructing SMFCs under aquaculture conditions by employing indigenous carbohydrates as substrates to enhance the removal efficiency of polycyclic aromatic hydrocarbons (PAHs) in sediment, as well as the correlation between PAHs removal and electricity generation in SMFCs. The results showed that adding glucose could allow SMFCs to generate more electrical power and increase the removal efficiency of PAHs (by 57.2% for naphthalene, 41.3% for acenaphthene, and 36.5% for pyrene). In addition, starch enhanced PAHs removal by 49.9%, 35.8%, and 31.2%, respectively, whereas cellulose enhanced removal by 44.3%, 29.3%, and 26.9%, respectively. Pearson correlation coefficients between the level of electrical power generated and the removal masses of the three PAHs were 0.485, 0.830**, and 0.851**. Thus, the use of SMFCs could be an effective approach for PAH treatment in aquaculture, and the electrical power generated could be used as an in-situ indicator for the biodegradation rate of SMFCs.

Automated summary

The study found that sediment microbial fuel cells (SMFCs) constructed under aquaculture conditions using indigenous carbohydrates as substrates can significantly enhance the removal efficiency of polycyclic aromatic hydrocarbons (PAHs). Different carbohydrates have varying effects on PAH removal, and there is a correlation between the electricity generated and the removal masses of PAHs.