Electrochemical conversion of corn stover lignin to biomass-based chemicals between Cu/Ni Mo Co cathode and Pb/PbO 2 anode in alkali solution

Carboxylic Acids Production via Electrochemical Depolymerization of Lignin

“…Electrochemical characterization of lignin depolymerization was conducted by means of pure electrochemical methods such as chronamperometry, cyclic voltammetry and impedance spectroscopy. Furthermore, parameters such as current density, electrode material and geometry are found to play an important role for the yields and the selectivities ,…”

Electrochemical Lignin Conversion

“…There are three primary electro-oxidation strategies, namely direct, indirect, and electrical-chemical combination reactions ( Figure 2). In direct electrooxidation, a heterogeneous catalyst (e. g., Ni, [6][7][8][9][10] PbO 2, [11,12] or RuO 2 [13,14] ) is usually directly used as the electrode or immobilized on the surface of the electrode, and the catalytic depolymerization process and electrolysis happen simultaneously on the electrode surface. These electrochemical processes are limited by surface catalysis, [9] so the solubility of lignin, proton/electron conduction, and electrochemical stability of the electrolyte become key challenges.…”

“…[30] The reduction of 1Ga to 1G was also detected by a reduction peak (c') at 1.1 V. Compound 1G is converted to the α-carbonyl compound 2G via the ECEC mechanism (E = electron transfer and C = chemical step) in four steps ( Figure 3C): E1) first oxidation step by single-electron transfer; C1) deprotonation at C α À H step by a chemical process; E2) second oxidation step by single-electron transfer; C2) deprotonation at C α À OH step by a chemical process. [30] Electrochemical degradation of lignin was successfully achieved in many direct electrooxidation processes, [14,[31][32][33][34][35] in which CÀ O or CÀ C cleavage were involved. Mechanistic studies found the CÀ O bond of the abundant β-O-4 aryl ether linkage could be cleaved using electrocatalysts.…”

“…(10)] can facilitate lignin degradation [Eq. (12)]. [86] Pb=PbO 2 anode : The possible pathways of lignin depolymerization by anode oxidation and electro-generated ROS oxidation.…”

“…[108] Only limited efforts have focused on hybrid electro-oxidative and electroreductive depolymerization of lignin. [34,59,87,152,153] The advantage of a hybrid approach results from simultaneous generation of reactive oxygen species and hydrogen in situ, which can be used for electro-oxidation and electro-reduction of lignin and its intermediates. [59] Li and co-workers investigated a hybrid electrochemical degradation of bamboo lignin using a Cu cathode and Pb/PbO 2 anode in sodium hydroxide solution, [34] and identified vanillin, syringaldehyde and p-coumaric acid as the main products.…”