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

• Published in: Industrial crops and products 2019-11, Vol.140, p.111604, Article 111604
• Main Authors: de Araújo Padilha, Carlos Eduardo, da Costa Nogueira, Cleitiane, de Santana Souza, Domingos Fabiano, de Oliveira, Jackson Araújo, dos Santos, Everaldo Silvino
• Format: Article
• Language: English
• Subjects: Biomass; Biosurfactant; Enzymatic hydrolysis; Lignin; Liquor recycling; Reuse
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2019.111604

[Display omitted] •Production of ethanol, lignin and rhamnolipids from the valorization scheme of green coconut fibre (GCF) and glycerol.•Glycerol-based pretreatments promoted high delignification and cellulose enrichment.•Reuse of black liquor slightly affected the sugar release/fermentability of pretreated GCF.•The produced rhamnolipids presented good emulsifying capacity. 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.