Bioremediation and bioelectricity from Himalayan rock soil in sediment-microbial fuel cell using carbon rich substrates

Abstract

In sediment microbial fuel cells soil microbes are responsible for bioremediation by degradation of pollutants present in it. The microbial metabolism produces bioelectricity in the process. This work reports the use of Himalayan rock soil for such evaluations. Three substrates including organic matter, glucose and sucrose were utilized to evaluate its feasibility. Open circuit voltage was achieved was highest with glucose as substrate at 500 ± 15 mV. The electrode distances were changed to evaluate its effect on the bioelectricity production at 2, 3, 4, and 6 cm respectively. The study also showed the survival of electrogenic microbes in acidic environment of the soil. Carbon oxidation rates were reported for each of the s-MFC reactors with the three substrates. 0.105 mmol C/m−2 d−1 for the organic matter, 0.689 mmol C/m−2 d−1 for glucose, and 0.507 mmol C/m−2 d−1 for sucrose. This shows the ability of the soil microbes to oxidize the soil complexes by degrading it and release energy. Additionally, FTIR analysis confirmed the potential for degrading soil carbonates, nitrates, and other organic substances for each of the substrate-based s-MFC. This suggests the use of s-MFCs for remediation of pollutants that can be difficult to break by the conventional method and the production of useful energy from the waste.