Bioconversion of switchgrass: Identification of a leading pretreatment option based on yield, cost and environmental impact

Glucose and ethanol yields showed that methanol was the most effective pretreatment chemical at 1 mol L−1, producing 230 g of glucose and 340 cm3 of ethanol kg−1 of feedstock with a 97% conversion rate. Pretreatment employing sodium hydroxide was found to be the least effective, with cellulose to glucose conversion rates of 38% and 62% following simultaneous saccharification and fermentation (SSF). In general, SSF significantly increased cellulose conversion rates, up to 32% for some samples. At 0.55 € kg−1 glucose and 0.50 € L−1 ethanol methanol was also found to be the most cost effective pretreatment technique compared to sodium hydroxide at 1.96 € kg−1 glucose and 7.94 € L−1 ethanol.