Enhanced cello-oligosaccharides production from cellulose hydrolysis in molten salt hydrate over lignin-based hyper-cross-linked polymer (LHCP) adsorption.

Selective hydrolysis of crystalline cellulose to cello-oligosaccharides in molten salt hydrates (MSHs) is a promising method for valorization of lignocellulose. However, the by-products derived from cellulose hydrolysis can facilitate cello-oligosaccharide degradation and decrease its selectivity. To address this issue, lignin-based hyper cross-linked polymers (LHCPs) were prepared to in situ adsorb by-products during hydrolysis and thus prevent cello-oligosaccharides from degradation. The synthesized LHCP‐33%, with a high lignin content of 33%, showed a remarkable surface area of 708.7 m2 g−1 and good hydrophilicity, exhibiting a promising adsorption capacity of 340 mg g−1 towards 5-hydroxymethylfurfural (5-HMF), which is supposed to be the major cellulose-derived by-product. We showed that 5-HMF adsorption was driven by the formation of CH-π bonds between 5-HMF and aromatic rings on LHCP. When LHCP‐33% was employed in cellulose hydrolysis, the yield of cello-oligosaccharide can be efficiently enhanced from 39.5% to 78.2%. This work offered a new application of lignin in enhanced cello-oligosaccharide production from cellulose. [Display omitted] • 78.2 % yield of cello-oligosaccharide can be selectively produced from crystalline cellulose saccharification via in situ adsorption of by-products on lignin-based hyper cross-linked polymer (LHCP). • The synthesized LHCP shows a high surface area and good hydrophilcity which is beneficial for by-products adsorption. • The adsorption of hydrolysis-derived 5-hydroxymethylfurfural (5-HMF) on LHCP is driven by the formation of CH-π bonds rather than hydrogen bonds. • This approach provides a new alternative in utilization of lignin for high-valued cello-oligosaccharide production from cellulose. [ABSTRACT FROM AUTHOR]