Production of <i>p</i>-Coumaric Acid from Corn GVL-Lignin

Abstract

Following biomass fractionation of corn stover using γ-valerolactone (GVL) pretreatment, the resulting lignin stream was subjected to base hydrolysis reactions to achieve the isolation of pcoumaric acid (pCA) from p-coumarate esters present as pendent groups on the lignin. pCA was produced from 5-g-scale experiments in crude yields of 8.3 wt % with 95% purity and, following a straightforward purification using liquid–liquid extraction and crystallization from water, yielded crystalline pCA in 4.8 wt % yield with 97% purity; a methodology to realize 99.5% purity is demonstrated. Because of the mild saponification, the remaining lignin residue retains its value as a feedstock for oxidative or hydrogenolytic deconstruction or as a fuel for energy production in the biorefinery.