In-situ Cr(VI) reduction with electrogenerated hydrogen peroxide driven by iron-reducing bacteria.
Cr(VI) was reduced in-situ at a carbon felt cathode in an air-cathode dual-chamber microbial fuel cell (MFC). The reduction of Cr(VI) was proven to be strongly associated with the electrogenerated H(2)O(2) at the cathode driven by iron-reducing bacteria. At pH 2.0, only 42.5% of Cr(VI) was reduced after 12h in the nitrogen-bubbling-cathode MFC, while complete reduction of Cr(VI) was achieved in 4h in the air-bubbling-cathode MFC in which the reduction of oxygen to H(2)O(2) was confirmed. Conditions that affected the efficiency of the reduction of Cr(VI) were evaluated experimentally, including the cathodic electrolyte pH, the type of iron-reducing species, and the addition of redox mediators. The results showed that the efficient reduction of Cr(VI) could be achieved with an air-bubbling-cathode MFC.
Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou, China.
Liang
L
Liu
Yong
Y
Yuan
Fang-bai
FB
Li
Chun-hua
CH
Feng
D001673:Biodegradation, Environmental; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D002857:Chromium / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004563:Electrochemistry / Q000379:methods; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000378:metabolism*; D007711:Klebsiella pneumoniae / Q000378:metabolism*; D010084:Oxidation-Reduction; D020592:Shewanella / Q000378:metabolism*
D002857:Chromium; D006861:Hydrogen Peroxide; D007501:Iron