Sugar yields from dilute sulfuric acid and sulfur dioxide pretreatments and subsequent enzymatic hydrolysis of switchgrass

► Comparative data on dilute acid and sulfur dioxide pretreatment of switchgrass. ► Sugar yields were sensitive to pretreatment conditions. ► Dilute acid pretreatment at log CS of 1.6 gave the highest sugar yield of 86%. ► Sulfur dioxide pretreatment at log CS of 1.7 gave the highest sugar yield of 87%.