Improving the economy of lignocellulose-based biorefineries with organosolv pretreatment

Abstract

Lignocellulose-based processes for production of value-added products still face bottlenecks to attain feasibility. The key might lie on the biorefining of all lignocellulose main polymers, that is, cellulose, hemicellulose and lignin. Lignin, considered an impediment in the access of cellulose and normally considered for energy recovery purposes, can give a higher contribution towards profitability of lignocellulosic biorefineries. Organosolv pretreatment allows selective fractionation of lignocellulose into separate cellulose-, hemicellulose- and lignin-rich streams. Ethanol organosolv and wood substrates dominated the research studies, while a wide range of substrates need definition on the most suitable organosolv pretreatment systems. Techno-economic and environmental analyses of organosolv-based processes as well as proper valorization strategies of the hemicellulose-rich fraction are still scarce. In view of dominance of ethanol organosolv with high delignification yields and high-purity of the recovered cellulose-rich fractions, close R & D collaboration with 1st generation ethanol plants might boost commercialization.

Keywords: Biorefineries; Lignin; Lignocellulosic materials; Organosolv pretreatment; Selective fractionation.