A novel biorefinery concept based on marginally used halophyte biomass

Abstract

Halophytes have major potential in biorefinery as these salt tolerant crops have prospects as an alternative biomass to meet energy demands and provide value-added products with reduced effects in terms of food security and environmental damage when compared to other crops. In this study, we investigated the effects of organosolv pretreatment process parameters on the fractionation of residual fibers from pressed Salicornia ramosissima and how it affects the fractions of cellulose, lignin, and hemicelluloses. Pretreated pulps contained as high as 48.95% w/w cellulose, a 2.9-fold increase from the untreated fibers. The delignification of pulp was as high as 75.01% and hemicellulose removal reached 96.38%. The hemicellulose fractions contained as high as 78.49% oligomers and we identified up to 30.4% linear xylooligosaccharides in the composition. The majority of the fragments of hemicelluloses had molecular weights lower than 1000 Da. Isolated lignin samples had in most cases very low sugar and ash contamination with a reduced molecular weight. The typical G-, S-, and H-type aromatic units were detected in the lignin, together with β-O-4′, β-5′, β-β′, and dibenzodioxocine links. The results suggest a novel applicability of S. ramosissima in a biorefinery context with fractionation deriving building blocks for value added products.