Combination of Autohydrolysis and Catalytic Hydrolysis of Biomass for the Production of Hemicellulose Oligosaccharides and Sugars

Léa Vilcocq,Luis C Duarte,Florbela Carvalheiro,Patrick Jame,Agnès Crepet

doi:10.3390/reactions3010003

Abstract

Three different types of biomass sourced from forestry waste (eucalyptus residues), agricultural waste (wheat straw), and energy crop (miscanthus) were used as starting materials to produce hemicellulosic sugars, furans (furfural and hydroxymethylfurfural), and oligosaccharides. A two-step hybrid process was implemented; biomass was first autohydrolysed without any additive to extract hemicelluloses and dissolve it in water. Then, the hydrolysate was treated with a solid acid catalyst, TiO2-WOx, in order to achieve hydrolysis and produce monomeric sugars and furans. This article investigates the role of the biomass type, autohydrolysis experimental conditions, polymerisation degree and composition of hemicelluloses on the performance of the process coupling autohydrolysis and catalytic hydrolysis. The highest global yields of both oligosaccharides and monomeric sugars were obtained from Eucalyptus (37% and 18%, respectively).

Highlights

Considering fossil resource depletion and global climate change, the need for alternative sources of carbon is on the raise
These values are in agreement with the composition of biomass reported in the literature: average hemicellulose content was reported to be 23–60% for woody biomass, 33% for wheat straw, and 26–40% for herbaceous biomass [57]
More xylose was obtained from eucalyptus residues, and more arabinose from wheat straw and miscanthus

Summary

Introduction

Considering fossil resource depletion and global climate change, the need for alternative sources of carbon is on the raise. Lignocellulose, the main component of non-edible terrestrial biomass, is a major source of renewable carbon [1]. The degree of polymerization (DP) of hemicelluloses ranges from 50 to 300 [4,5] Their valorization can lead to numerous value-added compounds [6]; oligosaccharides (OS) can be used as texture additives or probiotics in the agrifood industry [7], rare sugars can be used as sweeteners in flavor industry [2], and xylose can be hydrogenated to xylitol [8], a widely used compound in food industry and one of the Top 12 molecules in a famous DoE report [9], or dehydrated to furfural, a building block for many processes [10]

Methods

Results

Discussion

Conclusion