Quantitative comparison on delignification performance of pretreatment technologies of lignocellulosic biomass for enzymatic saccharification

Abstract Pretreatments for delignification are necessarily required for the enzymatic saccharification of lignocellulosic biomass. However, in current literature various pretreatment approaches have been applied to same kinds of biomass. In order to find the optimum pretreatments for biomass with various lignin contents, a quantitative comparison has been made on the delignification performance of 15 categories of pretreatments in this study. In total, 1729 series of biomass, cellulose, hemicellulose, and lignin recovery data were collected from 214 relevant studies. The box-plots and Cate-Nelson-like graphs were applied for the analysis. The results showed that among the 15 pretreatment categories, alkali, oxidation, organic solvent, and multiple-step pretreatments worked better to remove more lignin while recover more cellulose. Moreover, alkali pretreatments tended to more evidently increase saccharification efficiency by about five folds on average than the other three pretreatments.