Unveiling the lithium deintercalation mechanisms in spent lithium-ion batteries via sulfation roasting.

Recovery of valuable metals from spent lithium-ion batteries (LIBs) is of great importance for resource sustainability and environmental protection. This study introduced pyrite ore (FeS2) as an alternative additive to achieve the selective recovery of Li2CO3 from spent LiCoO2 (LCO) batteries. The mechanism study revealed that the sulfation reaction followed two pathways. During the initial stage (550 °C-800 °C), the decomposition and oxidation of FeS2 and the subsequent gas-solid reaction between the resulting SO2 and layered LCO play crucial roles. The sulfation of lithium occurred prior to cobalt, resulting in the disruption of layered structure of LCO and the transformation into tetragonal spinel. In the second stage (over 800 °C), the dominated reactions were the decomposition of orthorhombic cobalt sulfate and its combination with rhombohedral Fe2O3 to form CoFe2O4. The deintercalation of Li from LCO by the substitution of Fe and conversion of Co(III)/Fe(II) into Co3O4/CoFe2O4 were further confirmed by density functional theory (DFT) calculation results. This fundamental understanding of the sulfation reaction facilitated the future development of lithium extraction methods that utilized additives to substantially reduce energy consumption.

MiR-199a-3p Restrains Foaming and Inflammation by Regulating RUNX1 in Macrophages.

MiR-199a-3p was reported decreased in serum of coronary heart disease patients and human atherosclerotic plaques. This study aims to investigate the roles of miR-199a-3p in atherosclerosis (AS). AS was induced in ApoE-/- mice via high fat diet for 12 weeks. Oxidized low density lipoprotein (ox-LDL) was used to induce foaming in RAW264.7 cells. The expression level of miR-199a-3p was decreased in aortas of AS mice and ox-LDL-treated macrophages. Oil red O staining, ELISA, flow cytometry, and western blot results demonstrated that miR-199a-3p mimics restrained ox-LDL-induced lipid accumulation, foaming, and inflammation in RAW264.7 cells, while miR-199a-3p inhibitor played opposite roles. Runt-related transcription factor 1 (RUNX1), a pro-inflammatory factor, was identified as a target of miR-199a-3p, and its expression was downregulated by miR-199a-3p. RUNX1 was increased in macrophages from aortas and peripheral blood of AS mice. Ox-LDL-induced inflammation and lipid accumulation were aggravated by RUNX1, and the effects of miR-199a-3p were antagonized by ectopic expression of RUNX1 in RAW264.7 cells. The phosphorylation of signal transducer and activator of transcription 3 (STAT3) was inhibited by miR-199a-3p and enhanced by RUNX1. In conclusions, we demonstrated that miR-199a-3p alleviated ox-LDL-induced foaming and inflammation by downregulating RUNX1 expression and deactivating STAT3 signaling in macrophages. These findings may provide novel targets for treatment of AS.

UV/ozone induced physicochemical transformations of polystyrene nanoparticles and their aggregation tendency and kinetics with natural organic matter in aqueous systems.

Once discharged into the environment, plastics debris are unavoidably subjected to natural weathering processes. Unfortunately, the impact of weathering on the aggregation tendency and kinetics of nanoplastics in complex environmental matrices is poorly understood. Here, we investigated the influence of weathering as induced by UV and O3 treatments, on the aggregation of polystyrene nanoparticles (PSNPs) in simulated waters containing representative organic molecules (humic acid, lysozyme, and alginate) and in natural waters. Results showed that UV/O3 weathering-induced physicochemical transformations of PSNPs, particularly the formation of oxygen-containing functional groups and the increase in hydrophilicity, altered the aggregation state of PSNPs to different extents. The presence of organic molecules destabilized the UV-aged PSNPs with strength of lysozyme > alginate > humic acid, owing to the decrease of sorption of macromolecules on their surface. Differently, the O3-aged PSNPs displayed strong stability in the absence or presence of organic molecules (except for lysozyme), probably due to steric repulsion arising from the leakage of endogenous organic matters. This work demonstrates that the aggregation behavior of PSNPs is determined by the complex interplays among weathering, natural organic matter, and solution chemistry, and provides significant insights into the fate and transport of PSNPs in realistic scenarios.