workers presented results on the electrocatalytic degradation of aspen lignin on Pb/PbO2 electrodes [35]. They identified 4-methylanisole as the main product of lignin oxidation, and hypothesized that hydroxide radicals (OH) oxidize lignin, a conclusion they reached by considering the earlier work of Quiroz and coworkers on oxidation ofp-nitrophenol on similar electrodes[36],i.e., its well-known activity toward generating OH radicals that can in turn oxidize other species. Hao and co-workers have recently investigated similar routes toward lignin degradation on PbO2
electrodes modified with [Fe(CN)6] 3-[37]. They quantified lignin degradation by UVevis, and found that removal efficiencies
approached 50% after 2 h