Case studies on sugar production from underutilized woody biomass using sulfite chemistry

We examined two case studies to demonstrate the advantages of sulfite chemistry for pretreating underutilized woody biomass to produce sugars through enzymatic saccharification. In the first case study, we evaluated knot rejects from a magnesium-based sulfite mill for direct enzymatic sugar production. We found that the sulfite mill rejects are an excellent feedstock for sugar production. In the second study, we presented SPORL (sulfite pretreatment to overcome the recalcitrance of lignocelluloses), a sulfite pretreatment process based on modified sulfite pulping for robust bioconversion of softwood forest residues. Sulfite pulping technology is well developed, with proven commercial scalability, and sulfite pretreatment is a strong contender for commercial adoption.