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The reductive catalytic fractionation (RCF) of lignocellulose, considering lignin valorization at design time, has demonstrated the entire utilization of all lignocellulose components; however, such processes always require catalysts based on precious metals or high‐loaded nonprecious metals. Herein, the study develops an ultra‐low loaded, atomically dispersed cobalt catalyst, which displays an exceptional performance in the RCF of lignocellulose. An approximately theoretical maximum yield of phenolic monomers (48.3 wt.%) from lignin is realized, rivaling precious metal catalysts. High selectivity toward 4‐propyl‐substituted guaiacol/syringol facilitates their purification and follows syntheses of highly adhesive polyesters. Lignin nanoparticles (LNPs) are generated by simple treatment of the obtained phenolic dimers and oligomers. RCF‐resulted carbohydrate pulp are more obedient to enzymatic hydrolysis. Experimental studies on lignin model compounds reveal the concerted cleavage of Cα–O and Cβ–O pathway for the rupture of β‐O‐4 structure. Overall, the approach involves valorizing products derived from lignin biopolymer, providing the opportunity for the comprehensive utilization of all components within lignocellulose. [ABSTRACT FROM AUTHOR]

The complexation confinement and in-situ crystallization strategies realized the effective anchoring of single atom Co in nitrogen-doped hollow carbon nanotubes, close to 100% elimination of tetracycline pollutants while achieving a record mineralization rate of 89.07%. [Display omitted] • Complexation confinement and in-situ crystallization confinement to fabricate single-atom Co. • The removal rate of tetracycline is close to 100% and the mineralization rate reached a record of 89.07% • Multiple perspective reveals the mechanism of ROS production and tetracycline degradation. • Graphite nitrogen regulates cobalt microenvironment to promote activation of PMS. Advanced-oxidation-process (AOPs) based on peroxymonosulfate (PMS) can provide strong reactive oxygen species (ROS) for the elimination of persistent-organic-pollutants (POPs), but the input of highly active environmentally friendly catalysts is the key. Here, confined cobalt was in-situ deposited on natural mineral halloysite nanotubes by Coulomb interaction, which further realizes the introduction of atomically-dispersed cobalt sites in nitrogen-doped hollow-carbon-nanotubes with large specific surface area. The constructed CoNC/NHCNTs-900 material can effectively activate PMS, resulting in the removal rate of tetracycline probe pollutants close to 100%, and the mineralization rate reached a record of 89.07%. Combined with density functional theory calculations, it was proved that the enrichment of graphite nitrogen is beneficial to regulate the microenvironment of Co and promote the adsorption and activation of PMS. In-depth tracking of the formation of ROS and the mechanism of tetracycline mineralization proved that CoNC/NHCNTs-900-driven AOPs degradation of POPs into a low-toxic species has reliability and practical significance. [ABSTRACT FROM AUTHOR]