Hydrothermal fractionation of woody biomass: Lignin effect on sugars recovery

• Published in: Bioresource technology 2015-09, Vol.191, p.124-132
• Main Authors: Yedro, Florencia M., Cantero, Danilo A., Pascual, Marcos, García-Serna, Juan, Cocero, M. José
• Format: Article
• Language: English
• Subjects: Biomass; Biorefinery; Carbohydrates - chemistry; Cellulose - chemistry; Chemical Fractionation - methods; Glucose; Hot Temperature; Hydrolysis; Lignin - chemistry; Polymers - chemistry; Polysaccharides - chemistry; Process flexibility; Spain; Wood - chemistry; Xylose
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2015.05.004

[Display omitted] •Hydrothermal fractionation of nine urban trees in a semicontinuous reactor.•The pH behavior is similar for different feedstocks.•Low content of lignin in raw material led to high hydrolysis of hemicelluloses.•The lignin content do not affect the cellulose hydrolysis.•Hemicelluloses and cellulose yield can be influenced by the structure of biomass. Subcritical water was employed to fractionate woody biomass into carbohydrates and lignin. Nine urban trees species (hardwood and softwood) from Spain were studied. The experiments were carried out in a semi-continuous reactor at 250°C for 64min. The hemicellulose and cellulose recovery yields were between 30%wt. and 80%wt. while the lignin content in the solid product ranged between 32%wt. and 92%wt. It was observed that an increment of solubilized lignin disfavored the hydrolysis of hemicelluloses. It was determined that the maximum extraction of hemicellulose was achieved at 20min of solid reaction time while the extraction of celluloses not exhibited a maximum value. The hydrolysis of hemicellulose and cellulose would be governed by the hydrolysis kinetic and the polymers accessibility. In addition, the extraction of hemicellulose was negatively affected by the lignin content in the raw material while cellulose hydrolysis was not affected by this parameter.