Using Isopropanol as a Capping Agent in the Hydrothermal Liquefaction of Kraft Lignin in Near-Critical Water

In this study, Kraft lignin was depolymerised by hydrothermal liquefaction in near-critical water (290–335 °C, 250 bar) using Na2CO3 as an alkaline catalyst. Isopropanol used a co-solvent with the objective of investigating its capping effect and capability reducing char formation. The resulting product, which mixture aqueous liquid, containing water-soluble organic compounds, char, had lower sulphur content than lignin. Two-dimensional nuclear magnetic resonance studies precipitates phase indicated that major bonds were broken. high molar masses organics, nevertheless, indicate extensive repolymerisation constituents once they have been from With increasing temperature, yield increased, although mass decreased. addition isopropanol increased products decreased well products, is indicative effect.