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Lignin valorization is essential for biorefineries to produce fuels and chemicals for a sustainable future. Today's biorefineries pursue profitable value propositions for cellulose and hemicellulose; however, lignin is typically used mainly for its thermal energy value. To enhance the profit potential for biorefineries, lignin valorization would be a necessary practice. Lignin valorization is greatly advantaged when biomass carbon is retained in the fuel and chemical products and when energy quality is enhanced by electrochemical upgrading. Though lignin upgrading and valorization are very desirable in principle, many barriers involved in lignin pretreatment, extraction, and depolymerization must be overcome to unlock its full potential. This Review addresses the electrochemical transformation of various lignins with the aim of gaining a better understanding of many of the barriers that currently exist in such technologies. These studies give insight into electrochemical lignin depolymerization and upgrading to value‐added commodities with the end goal of achieving a global low‐carbon circular economy. [ABSTRACT FROM AUTHOR]

The aerobic oxidative cleavage of 1,2-diols using a heterogeneous catalyst only based on earth-abundant metals manganese and sodium is reported for the first time. This reusable catalyst cleaves a variety of substrates into aldehydes or ketones with high selectivity. The reaction requires small catalytic loadings and is performed under mild conditions using ambient pressure O2 or air as the oxidant while producing water as the only by-product. Mechanistic investigations reveal a monodentate, two-electron oxidative fragmentation process involving a MnIV species. The eco-friendly, innocuous catalyst is compatible with a wide range of functional groups and conditions, making it highly competitive with classical reagents, such as periodic acid or lead tetraacetate, as a preferred method for activated 1,2-diols. [ABSTRACT FROM AUTHOR]