Electrochemical oxidative degradation is one of the most promising methods for generation of phenolic fine chemicals from the renewable feedstock lignin. High selectivity, no reagent waste, as well as cost efficiency are major advantages of this particular process. Application of Ni‐ and Co‐based anode materials led to the best results in respect to product yield and selectivity. Interestingly, repeated use of Ni foam electrodes for electrochemical oxidative degradation resulted in significantly increased yields of vanillin, indicating a modification of the electrode surface. In particular, activation of the electrodes by electrochemical treatment of black liquor enabled an activation which further increased the electrocatalytic activity as well as the yield of the aroma chemical vanillin up to more than 100 % compared to non‐activated Ni foam electrodes. Additionally, this activated electrode surface was analyzed via flowing atmospheric pressure afterglow surface desorption mass spectrometry (FAPA‐MS). The measurement revealed diaminotoluene as a major compound in this adsorption layer, which indicates that this compound is partly responsible for the activation process. Most likely, electrochemical induced deposition of such an organic surface layer enhances the lipophilicity of the electrode surface and increases the accessibility of relevant structural features of lignin particles to the anodic surface, resulting in a higher yield of the desired degradation product vanillin.

Limited fossil resources require innovative monomers and polymers derived from renewable feedstocks such as plant biomass.

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A biobased epoxy resin was prepared from tall oil fatty acids (TOFAs), a byproduct of the pulping industry. As free carboxylic acids compromise resin stability, TOFA was subjected to non-Kolbe decarboxylation to give alkenes upon loss of CO2. Thereby, the degree of unsaturation is significantly increased. This electrosynthetic protocol using an undivided cell setup and inexpensive graphite electrodes in a galvanostatic operation mode was scaled to a 1.5 L reactor, making use of electric current as a green and waste-free reagent. Simple, cost-efficient epoxidation using oxone subsequently gives an epoxy resin of low viscosity. Curing with anhydrides yields thermoset materials. Dynamic mechanical analyses and tensile and flexural tests were conducted to determine the effect of different curing agents on the thermomechanical properties. For methyl tetrahydrophthalic anhydride (MTHPA) and methyl-5-norbornene-2,3-dicarboxylic anhydride (MNA), good mechanical properties were observed, whereas dodecenyl succinic anhydride (DDSA) resulted in a brittle material with low T g.