A feasibility study on green biorefinery of high lignin content agro-food industry waste through supercritical water treatment

Tijana Adamovic, Dmitry Tarasov, Emre Demirkaya, Mikhail Balakshin, Maria José Cocero*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

1 Citation (Scopus)
24 Downloads (Pure)

Abstract

This work discusses hydrolysis of defatted grape in supercritical water (SCW) at 380 °C and 260 bar from 0.18 s to 1 s focusing attention to sugars recovery in the liquid phase of the product and detailed characterization of remaining solid phase enriched in polyaromatics (e.g. lignin, flavonoids, etc.). After the longest reaction time of 1 s, 56% of carbohydrates could be recovered in the liquid phase, as a result of carbohydrate hydrolysis. The high content of insoluble lignin in biomass (36%), acts as a mass transfer limitation and presents an important feature in the hydrolysis process, slowing down the conversion of carbohydrate fraction, as after the maximum time of 1s, 10% of carbohydrates still remained in the solid phase. Milled wood lignin, extracted from biomass and dioxane extract from the solid phase were characterized in order to understand the main structural changes during the SCW hydrolysis process. Dioxane (80%) extraction of solids produces a very complex mixture of lipophilic extractives, flavonoids and lignin with a certain amount of chemically linked carbohydrates. 2D NMR analysis of dioxane extract shows remarkably subtle changes in the amounts of main lignin moieties (β-O-4′, β-β’ (resinol) and β-5 (phenylcoumaran)). This subtle change of the main lignin structures is an important feature in the further valorisation of this sulfur-free lignin residue.

Original languageEnglish
Article number129110
Number of pages11
JournalJournal of Cleaner Production
Volume323
Early online date27 Sep 2021
DOIs
Publication statusPublished - 10 Nov 2021
MoE publication typeA1 Journal article-refereed

Keywords

  • 2D-NMR analysis
  • Carbohydrates
  • Circular economy
  • Grape seeds
  • Lignin
  • Polyaromatics

Fingerprint

Dive into the research topics of 'A feasibility study on green biorefinery of high lignin content agro-food industry waste through supercritical water treatment'. Together they form a unique fingerprint.

Cite this