Comparing the performance of Miscanthus x giganteus and wheat straw biomass in sulfuric acid based pretreatment

• Miscanthus required more energy/acid input in hydrolysis than wheat straw.
• Combining dilute sulfuric acid and steam explosion resulted in high C5 sugar yield.
• ADL lignin in miscanthus prevented efficient breakdown of fiber recalcitrance.

The objective of this study was to assess and compare the suitability of Miscanthus x giganteus and wheat straw biomass in dilute acid catalyzed pretreatment. Miscanthus and wheat straw were treated in a dilute sulfuric acid/steam explosion pretreatment. As a result of combining dilute sulfuric acid- and steam explosion pretreatment the hemicellulose hydrolysis yields (96% in wheat straw and 90% in miscanthus) in both substrates were higher than reported in literature. The combined severity factor (=CSF) for optimal hemicellulose hydrolysis was 1.9 and 1.5 in for miscanthus and wheat straw respectively. Because of the higher CSF value more furfural, furfuryl alcohol, 5-hydroxymethylfurfural and acetic acid was formed in miscanthus than in wheat straw pretreatment.