Valorization of green coconut fibre: use of the black liquor of organolsolv pretreatment for ethanol production and the washing water for production of rhamnolipids by pseudomonas aeruginosa ATCC 27583

Elsevier

2019-11

Biomass

Enzymatic hydrolysis

Liquor recycling

Reuse

Biosurfactant

Lignin

The present study proposes the production of ethanol, lignin and rhamnolipids from the valorization scheme of green coconut fibre (GCF) and glycerol. As expected, all pretreatments using 80% (w/w) glycerol and 1% (w/w) sulfuric acid promoted high delignification (> 60%) and good cellulose enrichment (> 50% w/w). The reuse of black liquor in the pretreatments apparently did not affect the glucose release (48.36–49.96 g/L) or the fermentability (22.62–29.64 g/L) of pretreated GCF at 20% (w/v) solid loading. Structural differences between recovered lignin from glycerol-based organosolv pretreatment and alkaline lignin were observed after spectroscopy and thermal stability analyses. In addition, the lignin precipitation water and washing water from the glycerol-based pretreatments of GCF were used in culture media preparation for Pseudomonas aeruginosa ATCC 27583. The production of rhamnolipids varied in the range of 0.57–1.25 g/L and presented greater emulsifying capacity than the rhamnolipids obtained from pure glycerol. Therefore, the methodology described in this study provides an unusual method for obtaining value-added products from organosolv pretreatment of lignocellulosic biomasses