Enzymatic Upgrading of AqSO Biorefinery Cellolignins for High Value Applications

Production of high-value chemicals and materials through plant biorefinery is a green alternative to the current petroleum-based industry. One of promising directions in a new biorefinery approach is the focus on ligno-carbohydrate functional hybrids (LCFH) to take advantage of the synergism between lignin and carbohydrates in specific high-value applications. AquaSolv Omni (AqSO) Biorefinery developed in our group is a green cost-efficient integrated biorefinery allowing for engineering of the reaction products in a wide range of composition, structure and properties. In addition, further engineering of LCFHs is possible combining AqSO Biorefinery with other traditional operations, such as enzymatic hydrolysis. However, in stick contrast to the traditional biorefineries, the goal of the enzymatic hydrolysis is the engineering of the resulted Cellolignins (lignins containing residual cellulose) rather than optimization of sugars/bioethanol yields. Depending on the AqSO process severity and enzyme (cellulase cocktail) load, LCFHs with lignin contents from 10 to 90 %, different lignin structures and properties were obtained. They were tested in replacement of phenol-formaldehyde (PF) wood adhesive using the automatic bond evaluation systems (ABES). It was demonstrated that the Cellolignins containing 20–40 % residual cellulose enhanced PF performance. The promising results of these application tests demonstrated a high potential of creating precursors for value-added products on the base of the AqSO biorefinery approach.