Skip to main content

Table 3 Experimental parameters

From: Energetic and biochemical valorization of cork boiling wastewater by anaerobic digestion

Parameter CBW AD0 AD3 AD6
pH 7.20 ± 0.10 8.23 ± 0.09 7.67 ± 0.02 7.52 ± 0.06
VFA (kg m-3) 0.215 ± 0.023 0.185 ± 0.036 0.178 ± 0.048 0.137 ± 0.013
Total phenols (mg mL-1) 1.20 ± 0.02 0.05 ± 0.00 0.90 ± 0.00 1.41 ± 0.02
OD (254 nm) 43.50 ± 0.22 8.41 ± 0.64 29.08 ± 0.66 43.96 ± 0.00
DPPH inhibition (%) 74.00 ± 0.84 78.90 ± 0.42 76.07 ± 1.56 80.80 ± 1.06
ECa50 (antiradical activity) 7.20 ± 0.11 2.22 ± 0.08 5.90 ± 0.08 8.74 ± 0.06
Conductivity (mS cm-1) 1.50 ± 0.10 4.00 ± 0.11 4.60 ± 0.00 5.40 ± 0.11
  1. aAntiradical activity defined as the amount of antioxidant (expressed as μg of total polyphenols) necessary to decrease the initial DPPH concentration by 50%. Values presented as an average ± standard deviation. AD0, blank anaerobic digestion assay; AD3, anaerobic digestion assay at 3 kg COD m-3 of CBW; AD6, anaerobic digestion assay at 6 kg COD m-3 of CBW; CBW, cork boiling wastewater, reactor influent; DPPH, 2,2-diphenyl-1-picrylhydrazyl; EC50, half maximal effective concentration; OD, optical density; VFA, volatile fatty acid.