Fig. 4From: Conversion of H2 and CO2 to CH4 and acetate in fed-batch biogas reactors by mixed biogas community: a novel route for the power-to-gas conceptThe initial (red) and final (blue) pH in the liquid phase of the reactors received mmole, respectively. α-cellulose (0.3 g) was added as substrate at the start of the experimentBack to article page