ie9b06607_si_001.pdf (4.88 MB)
Hydrotropic Solutions Enable Homogeneous Fenton Treatment of Lignin
journal contribution
posted on 2020-02-24, 15:35 authored by Robert
G. Keller, Davide Di Marino, Malte Blindert, Matthias WesslingIn
biorefineries, renewable resources are converted to value-added
chemicals. However, lignin is often only thermally valorized. In this
work, we propose an integrated process where lignin is extracted from
beech wood by a thermal autoclave pretreatment in a hydrotropic solution.
With increasing pretreatment temperature, we find a rising lignin
recovery of close to 90% at 200 °C. Subsequently, the hydrotropic
solution enables a homogeneous Fenton process as lignin can be dissolved
at acidic pH values. While lignin is degraded, we demonstrate a feasible
in situ extraction of low-molecular-weight aromatics such as p-cumenol. The proposed process proves to be a viable source
for valuable compounds, with up to 30% yield of organic acids based
on the initial lignin concentration. Consequently, the integrated
process described herein encompasses resource efficiency, as only
one solvent is used for pretreatment and degradation, and raw material
efficiency with a lignin extraction yield close to 90%.