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The recovery of iron phosphate from the leaching slag of used lithium iron phosphate cathode materials is a crucial step to achieve closed-loop recovery of lithium iron phosphate, which has not yet been effectively accomplished. In the study, ultrasonic-assisted sulfuric acid leaching was used to remove impurities in the iron phosphate, to meet the stringent impurity content requirements for battery-grade iron phosphate regarding impurity content. Optimization of leaching conditions involved a sulfuric acid concentration of 0.2 mol·L-1, acid-leaching time of 30 min, power of 50 W, and reaction temperature of 80℃. Under these conditions, the removal efficiencies of Cr, Cu, Ni, and Zn in iron phosphate were 26.09%, 83.0%, 75.9%, and 96.3%, respectively. Simultaneously, the content of impurity elements Cr and Zn concurred with the standard for battery-grade iron phosphate (HG/T 4701-2021), with both 50 ppm and 10 ppm contents. The leaching results indicated the effectiveness of ultrasound in enhancing the removal of impurity elements in iron phosphate within a sulfuric acid solution. Further analyses, including XRD, particle size, TEM, and XPS indicated that the surface of the iron phosphate particles cavitated after ultrasonic acid leaching, resulting in the formation of numerous pores. Additionally, particle collisions led to a reduction in particle size, with no generation of by-products during the process. This innovative approach not only contributed to the removal of impurity elements but also provided insights into the reuse of leaching slag (iron phosphate) and offered guidance for the recovery of metals from waste lithium iron phosphate cathode materials.

The recovery of metals from the cathode material or used lithium-ion batteries is of both environmental and economic importance. In this study, stepwise precipitation by acid leaching was used to separate and recover lithium, iron, and manganese from the mixed LiFePO4/LiMn2O4 cathode material. The thermodynamic properties of the lithium, iron, and manganese metal phases, especially the stability range, were analyzed using Eh-pH diagrams. The leaching system with sulfuric acid and hydrogen peroxide released Fe3+, Mn2+, and Li+ ions from the cathode material. Fe3+ in the leaching solution was precipitated as Fe(OH)3 and finally recovered as Fe2O3 after calcination. Mn2+ in the leaching solution was recovered as MnCO3. The remaining Li+-rich solution was evaporated and crystallized into Li2CO3. The purity of the recycled MnCO3 and Li2CO3 met the standard of cathode materials for lithium-ion batteries. XRD and XPS analysis showed that the main phase in the leaching residue was FePO4. This process can be used to separate and recover metals from mixed waste lithium-ion battery cathode materials, and it also provides raw materials for the preparation of lithium-ion battery cathode materials.

The thermodynamic properties of impurity components in silicon solutions play an important role in the chemical removal process to the metallurgical route. In this paper, the component activity coefficients and interaction parameters of dilute silicon solutions were estimated by the molecular interaction volume model (MIVM). The activity coefficients (γi) of component i in dilute binary Si-i and ternary Si-i-j solutions at 1687-1873 K were firstly calculated. The concentration dependences of the interaction parameter and activity coefficient were also obtained. The self-interaction parameters (εi,i) for Si-i system were obtained as εB,B= -2.728-362.031/T, εAl,Al = 2.157-1876.776/T, εFe,Fe= -4.842+14445.926/T and εP,P = -2.543+13767.036/T. At the same time, the interaction parameters among components B, Al, and Fe in dilute ternary Sii- j solutions were also derived as εFe,B=-1.2758-2946.306/T, εAl,B = 0.7467-9765.9298/T and εFe,Al= -1.39677+3319.6803/T. Most important of all, the temperature dependences of the interaction parameters and activity coefficients in dilute Si-i and Si-i-j solutions with a certain i or j concentration were deduced. The results show that the predicted self-interaction parameters of B, Al, Fe, and P in binary silicon solutions reasonably agree with the experimental data. This further shows that MIVM is of reliability and can be expanded to a multi-component dilute silicon solution.

The interactions among impurity components in Si-based solution are the important thermodynamic parameters for the purification of silicon materials. A “same concentration” method was used to determine the activity interaction coefficients of Fe to B and Al to B in the silicon solution. Fe and Al were respectively dissolved into the binary Si-B solution at 1723 K with the holding time of 5 h, 7 h, 9 h, and 11 h. The equilibrium concentrations of Fe, B in the Si-B-Fe system and Al, B in the Si-B-Al system were determined. The interaction coefficients of Fe to B and Al to B were obtained by fitting the solubility data of B, Fe, and Al. The solubility relationships between B and [%Fe], and between B and [%Al] were obtained, respectively. It was found by the SEM and EPMA pictures of the samples that the third component Fe or Al added to the binary Si-B solution was alloyed, which verifies the accuracy of the experimental determination results. The significance of the activity interaction coefficient of B on boron removal from industrial silicon was analyzed.

Copyright of Journal of Mining & Metallurgy. Section B: Metallurgy is the property of Journal of Mining & Metallurgy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mining & Metallurgy. Section B: Metallurgy is the property of Journal of Mining & Metallurgy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

OBJECTIVE: Experimental autoimmune myocarditis (EAM) is characterized by pronounced macrophage infiltration, cardiac necrosis, and cardiac fibrosis. Our previous studies have demonstrated that suppressed androgen receptor (AR) enables anti-inflammation to promote tissue repair by decreasing M1 macrophages and increasing M2 macrophages in an EAM model. Given that autophagy mediates inflammatory response in macrophages, we investigated whether AR inhibition executes its protective role in inflammation through the autophagy pathway in EAM. MATERIALS AND METHODS: To determine whether AR inhibition can perform its anti-inflammatory effects by upregulating autophagy, we pre-treated mice with 3-methyl adenine (3-MA), a pharmacological inhibitor of autophagy. Immunofluorescence assay and Western blot were used to detect autophagy levels and autophagy activity in five different groups. Immunofluorescence marked F4/80 and LC3 to illustrate the autophagy level in macrophages. TUNEL assays were used to detect the apoptosis level in heart tissue of five different groups. RESULTS: We demonstrated that AR inhibition resolves injury with sustained inhibition of inflammatory cytokines associated with enhanced autophagy, especially in macrophages. Increased LC3II/I expression corroborated complete autolysosome formation detected by electron microscopy and correlated with degradation of SQSTM1/p62 in the AR inhibition group by Western blot. These effects could be reversed within 3-MA, a pharmacological inhibitor of autophagy. Specifically, pharmacological inhibition of autophagy increased apoptosis and inflammation, which could be attenuated by AR inhibition. CONCLUSIONS: AR inhibition alleviates the inflammatory response and tissue apoptosis by enhancing autophagy, especially in macrophages. [ABSTRACT FROM AUTHOR]

A new solid acid catalyst SO42−/ZrO2‐CeO2 (SZC) was prepared by co‐precipitation method and used in biodiesel production. Different from considering several parameters in available literatures, the effect of all 10 parameters in the preparation process on the catalytic activities of SZC were studied systematically and comprehensively. The catalytic performance was tested by the conversion of Jatropha oil fatty acids (CFA) in esterification. TG, XRD, BET, TEM, NH3‐TPD, FTIR were used to characterize the catalyst aiming to analyze the influence mechanisms of each factor. The results indicated that the surface area and acidity of sulfated zirconia increased by doping of Ce. The most important preparation parameters included loading amounts of CeO2, aging time, and calcination temperature, their proper values were 5%, 21 h, 773 K, respectively. Moreover, novel findings included: the ammonia concentration influences the acid strength of catalyst which was more important than the amount of acid sites for the catalytic activities and drying before calcination was a necessary step. [ABSTRACT FROM AUTHOR]

The -delayed particle emission from the exotic nucleus Si has been studied using a detection system with silicon array and clover-type high-purity germanium (HPGe) detectors. The -delayed charged-particle spectrum and -ray spectrum were identified. The half-life of Si has been determined. A new -delayed proton branch with an energy of 3811keV was observed. The -delayed two-proton emission was confirmed. [ABSTRACT FROM AUTHOR]