Solvolytic Deconstruction of Lignin and Upgrading to Renewable Chemicals

Abstract

Solvolysis of industrial cornstover lignin was carried out in methanol and ethanol to deconstruct lignin into monomers and small oligomers using various reactor configurations. We demonstrate that it is possible to overcome the limitations inherent to batch reactors by carrying out the solvolytic deconstruction in flow-through reactors as they allow for the continuous removal and rapid cooling of the products. The yield of monomers and solvent-soluble products were higher for flow-through reactors under all tested reaction conditions. We also investigated the effects of various reaction parameters and phase of solvent (sub-and supercritical) on the distribution and yield of lignin-derived products using complementary characterization techniques. p-Coumaric acid and ferulic acid were obtained as primary monomers with very high selectivity and yield for all tested reaction conditions. A maximum monomeric yield of 14.45 wt % was obtained at 250 ⁰C and 85 bar in ethanol. Subsequent upgrading of the deconstructed