Optimising the (Microwave) Hydrothermal Pretreatment of Brewers Spent Grains for Bioethanol Production

Figure 5

The impact of reaction temperature (120–200°C) and reaction time (1–10 min) at various solids loading during acid catalysed hydrothermal pretreatment of BSG on % theoretical glucose yields following enzymatic saccharification of the pretreated solid residue. (a) 30% solids loading, (b) 40% solids loading, and (c) 50% solids loading. Data are the mean ± SD of three replicate measurements. 1% HCl hydrothermal pretreatment utilized a Monowave 300 microwave synthesis reactor with G30 vessels (Anton Parr). Enzymatic saccharification of pretreated residue: 24 h incubation (50°C) using 200 mg residue to 40 mL of a 1 g/L Celluclast solution buffered to pH .

(a) 30% w/v solids loading

(b) 40% w/v solids loading

(c) 50% w/v solids loading