8-29: A state-of-the-art steam explosion unit at the Norwegian University of Life Sciences - Solubilization of carbohydrates, formation of inhibitors and analyses of complex samples

Efficient enzymatic or microbial degradation of lignocellulosic biomass necessitates some kind of pretreatment to make the carbohydrates more accessible. Steam explosion is known to be one of the most efficient and environmentally benign pretreatment methods. The severity of the pretreatment is determined by the residence time and the temperature in the high pressure reactor. Generally, harsher pretreatment conditions make the sugars in the biomass more accessible for hydrolysis. However, harsh conditions also lead to monosaccharide decomposition producing compounds such as HMF and furfural, which are potential inhibitors for microorganisms. Thus, optimum steam explosion conditions will be a compromise between carbohydrate accessibility and inhibitor formation. The high flexibility and high throughput associated with having an in house SE unit has prompted the buildup of a new analytical platform which makes efficient monitoring of different pretreatment conditions possible. We will present examples of the analytical tools that we use to characterize the outcomes of steam explosion treatments as well of subsequent hydrolysis and fermentation steps.