Fig. 1

Langmuir regression line of adsorption of the lignin samples from corn stover untreated and pretreated by liquid hot water of different pretreatment severities (S). Fitting curve: for control: Y = 0.1564x + 0.0226 (R ² = 0.916); for S = 3.6: Y = 0.0753x + 0.0099 (R ² = 0.9074); for S = 3.9: Y = 0.1264x + 0.0042 (R ² = 0.8494); for S = 4.2: Y = 0.1051x + 0.0029 (R ² = 0.9646)