Electroflotation enables treatment of effluents generated during pyrolytic biomass revalorization

Abstract Wastewater produced during biomass revalorization contains high organic load. Organic compounds generated during pyrolysis of biomass are hardly removed by conventional treatments. If sustainable treatment of these effluents can be enforced, biomass revalorization would be an excellent sustainable approach for energy production. This work explores the competitiveness of electroflotation as emerging electrochemically-driven separation technology using a scaled-up continuous-flow electroflotation reactor (CFER). Electrogeneration of gas bubbles drives the separation of hydrophobic organic compounds from aqueous solution. Experimental designed was employed to optimize the operational variables (i.e., applied current density and sodium chloride concentration) at different flow rates. Under conditions of 3.5 mA cm−2, 2.0 g L-1 of NaCl, and flowrate of 100 L h−1, complete decolorization of effluent was obtained with a total organic abatement of 55%. Chromatographic analyses demonstrated complete removal of phenolic compounds. These results identify electroflotation as suitable and promising pre-treatment to decrease the high-organic loads of pyrolytic wastewater.