Study on microbial reduction of vanadium matallurgical waste water

Abstract

The research employed microbial fuel cell (MFC) to domesticate dissimilatory metal reduction microorganisms, and to study the endurance to NaVO 3 of Rhodoferax ferrireducens ( R.f). The effects of concentration of NaVO 3, pH, and temperature on the reduction of V +5 have also been observed. The maximum current output of the MFC is 0.318 mA when there is no vanadium compound in the MFC. While adding 300 mg/L NaVO 3 into the anode chamber, the current output reached 0.6 mA, the reduction ratio of NaVO 3 is 72%, and the total electron recovery of MFC is 64%. When the main operation parameters are as follows: 30 °C, 150 rpm stirring speed, pH 7.5, and vanadium wastewater with 300 mg/L NaVO 3, the reduction rate of V +5 is 75.8%, and bacteria density reached 1.1 × 10 9 CFU/ml. The proper concentration of NaVO 3 in the wastewater promotes the formation of biofilm on the electrodes in MFC, and it also accelerates the rate of glucose conversion by the microbes.