title: Highly selective generation of vanillin by anodic degradation of lignin: a combined approach of electrochemistry and product isolation by adsorption.
abstract: The oxidative degradation of lignin into a variety of valuable products has been under investigation since the first half of the last century. Especially, the chance to claim this cheap, abundant and renewable source for the production of the important aroma chemical vanillin (1) was one of the major driving forces of lignin research. So far most of the developed methods fail in technical application since no viable concept for work-up is included. This work represents a combined approach of electrochemical conversion of Kraft lignin and product recovery by adsorption on a strongly basic anion exchange resin. Electrolysis conditions are optimized regarding reaction temperatures below 100 °C allowing operation of aqueous electrolytes in simple experimental set-up. Employing ion exchange resins gives rise to a selective removal of low molecular weight phenols from the strongly alkaline electrolyte without acidification and precipitation of remaining lignin. The latter represents a significant advantage compared with conventional work-up protocols of lignin solutions.
authors.affiliation: Institute for Organic Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Schmitt
authors.affiliation: Institute for Organic Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany ; BASF SE, GCN/ES-M311, 67056 Ludwigshafen, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Regenbrecht
authors.affiliation: Institute for Organic Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
authors.forename: Marius
authors.initials: M
authors.lastname: Hartmer
authors.affiliation: BASF SE, GCN/ES-M311, 67056 Ludwigshafen, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Stecker
authors.affiliation: Institute for Organic Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
authors.forename: Siegfried R
authors.initials: SR
authors.lastname: Waldvogel
keywords: adsorption; electrochemistry; lignin; nickel; renewable resources