The ion exchange resin-treated digestate was recycled as process water for ethanol
fermentation, with controls using DI water and digestate without treatment. Before
liquefaction of the cassava slurry, the pH was adjusted to 5.5-6.0 using 30wt% H2SO4
or 10 wt% NaOH as necessary. When resin-treated digestate was used, the pH of the
slurry was 5.53 and 6.08 before and after liquefaction (Table 2), and therefore no pH
adjustment was required