Preparation of lithium-ion battery anode materials from graphitized spent carbon cathode derived from aluminum electrolysis

Graphitized spent carbon cathode(SCC)is a hazardous solid waste generated in the aluminum electrolysis process.In this study,a flotation-acid leaching process is proposed for the purification of graphitized SCC,and the use of the purified SCC as an anode material for lithium-ion batteries is explored.The flotation and acid leaching processes were separately optimized through one-way experiments.The maximum SCC carbon content(93wt%)was achieved at a 90%proportion of−200-mesh flotation particle size,a slurry concentration of 10wt%,a rotation speed of 1600 r/min,and an inflatable capacity of 0.2 m^(3)/h(referred to as FSCC).In the subsequent acid leaching process,the SCC carbon content reached 99.58wt%at a leaching concentration of 5 mol/L,a leaching time of 100 min,a leaching temperature of 85°C,and an HCl/FSCC volume ratio of 5:1.The purified graphitized SCC(referred to as FSCC-CL)was utilized as an anode material,and it exhibited an initial capacity of 348.2 mAh/g at 0.1 C and a reversible capacity of 347.8 mAh/g after 100 cycles.Moreover,compared with commercial graphite,FSCC-CL exhibited better reversibility and cycle stability.Thus,purified SCC is an important candidate for anode material,and the flotation-acid leaching purification method is suitable for the resourceful recycling of SCC.

The Impact of Seasonal Variation on Clinical Pregnancy and Live Birth Rates in Assisted Reproductive Technology: A Retrospective Cohort Study in Hainan

Objective:To investigate the influence of season on live birth and clinical pregnancy rates,as well as assisted reproductive technology(ART)outcomes,in the Hainan region.Methods:Patients were categorized into four groups based on the dates of artificial insemination and transplantation:spring,summer,autumn,or winter.The main outcome measures were clinical pregnancy rates and live birth rates.Secondary outcomes included body mass index(BMI),oocyte number,two pronuclei(2PN)cleavage rate,total gonadotropin(Gn)dosage and days,age,2PN fertilization rate,sperm concentration,sperm PR rate,anti-Müllerian hormone(AMH),and endometrial thickness.Outpatient semen quality indicators included sperm PR rate,total sperm count,sperm concentration,and total sperm motility.Results:This retrospective cohort study analyzed 2,016 artificial insemination cycles and 1,783 ovarian retrieval cycles from January 2017 to October 2022,and assessed the semen quality of 6,651 outpatients from May 2017 to October 2022.In artificial insemination cycles,sperm PR rate and clinical pregnancy rate were highest in winter,with a statistically significant difference between groups(P<0.05).Clinical pregnancy rate was influenced by both age and sperm PR rate(P<0.05).In ovarian retrieval cycles,the winter group had significantly higher clinical pregnancy,2PN fertilization,and 2PN cleavage rates than the other groups.The autumn group had higher live birth rates,though not significantly different.Additionally,winter months showed higher total sperm concentration and total sperm number compared to other seasons.Conclusion:Seasonality affected clinical pregnancy and live birth rates in artificial insemination cycles but not in ovarian retrieval cycles in the Hainan region.These findings suggest that while there is no need to choose a specific season for ovarian retrieval cycles,artificial insemination in winter may be preferable for patients.