Solvent extraction and separation of cobalt from leachate of spent lithium-ion battery cathodes with N263 in nitrite media

To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines with Co(Ⅱ) to form an anion [Co(NO_(2))_(3)]^(-),and it is then extracted by N263.The extraction of Co(Ⅱ) is related to the concentration of NO_(2)^(-).The extraction efficiency of Co(Ⅱ) reaches the maximum of99.16%,while the extraction efficiencies of Ni(Ⅱ),Mn(Ⅱ),and Li(Ⅰ) are 9.27%-9.80% under the following conditions:30vol% of N263 and15vol% of iso-propyl alcohol in sulfonated kerosene,the volume ratio of the aqueous-to-organic phase is 2:1,the extraction time is 30 min,and1 M sodium nitrite in 0.1 MHNO_(3).The theoretical stages require for the Co(Ⅱ) extraction are performed in the McCabe–Thiele diagram,and the extraction efficiency of Co(Ⅱ) reaches more than 99.00% after three-stage counter-current extraction with Co(Ⅱ) concentration of 2544mg/L.When the HCl concentration is 1.5 M,the volume ratio of the aqueous-to-organic phase is 1:1,the back-extraction efficiency of Co(Ⅱ)achieves 91.41%.After five extraction and back-extraction cycles,the Co(Ⅱ) extraction efficiency can still reach 93.89%.The Co(Ⅱ) extraction efficiency in the actual leaching solution reaches 100%.

Photocatalytic Treatment of Microcystin-LR-Containing Wastewater Using Pt/WO ₃Nanoparticles under Simulated Solar Light

This study investigates the photocatalytic degradation of microcystin-LR (MC-LR) under simulated solar light using Pt modified nano-sized tungsten trioxides (Pt/WO3). Photocatalytic activity was higher during the degradation of MC-LR with Pt/WO 3 than with pure WO 3 or Ti O2 . The catalyst loading greatly affect the degradation performance. The rate of degradation is influenced by the initial pH of the reaction solution. This study also investigates the photocatalytic inactivation of cyanobacteria. The results show that the algal growth was successfully controlled by the Pt/W O 3 . This study suggests Pt/W O 3 photocatalytic oxidation with solar light is a promising treatment for water containing MC-LR.

Observation on Curative Effect of Self-made Wubeizi Decoction Combined with rhaFGF in Promoting Postoperative Wound Healing in Patients with Anal Fistula

[Objectives]To explore the curative effect of Self-made Wubeizi Decoction combined with recombinant human acidic fibroblast growth factor(rhaFGF)in promoting postoperative wound healing in patients with anal fistula.[Methods]A total of 82 patients with anal fistula who underwent anal fistula resection+use of setons in Luodian Hospital during January and March of 2020 were randomly divided into observation group and control group with 41 cases in each group.The control group was given rhaFGF external application regimen,and the observation group was treated with Self-made Wubeizi Decoction on the basis of the control group.After 3 weeks of treatment,the differences in curative effects of TCM syndromes were compared between the two groups.Besides,the changes in TCM symptom scores,inflammatory mediators[interleukin-12(IL-12),tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ)],anorectal functions[anal resting pressure(ARP),maximal systolic pressure(MSP)and maximum tolerated volume(MTV)of the anal canal],quality of life[GQOLI-74 scores]were compared.[Results]After 3 weeks of treatment,the total effective rate of the observation group was significantly higher than that of the control group(P<0.05);the levels of TCM symptom scores,IL-12,TNF-α,IFN-γ,ARP,MSP,and MTV in both groups were significantly lower than those before treatment,and these levels in the observation group was significantly lower than that in the control group at the same time(P<0.05).The GQOLI-74 scores of both groups were significantly higher than those before treatment,and the observation group was significantly higher than the control group(P<0.05).[Conclusions]The Self-made Wubeizi Decoction combined with rhaFGF therapy has a significant effect in promoting postoperative wound healing in patients with anal fistula.It can effectively inhibit the local inflammation of patients,facilitate the recovery of anorectal function and improve the quality of life,thus has high clinical application value.

Enhanced Biohydrogen Production by Accelerating the Hydrolysis of Macromolecular Components of Waste Activated Sludge Using TiO₂Photocatalysis as a Pretreatment

The effects of TiO2 photocatalysis on the hydrolysis of protein of waste activated sludge (WAS) and its biodegradability were investigated in this study. After 12-h UV irradiation, the removal ratio of protein by TiO2 photocatalysis reached 98.1%. The optimal condition for photocatalytic degradation of protein is TiO2 dosage of 5.0 mg·L–1 under 2.4 w·m–2 UV light irradiation. TiO2 photocatalysis in comparison with other pretreatments obviously accelerated the hydrolysis of WAS and improved the conversion of total COD (tCOD) to soluble COD (sCOD). The sCOD/tCOD ratio of WAS pretreated by TiO2 photocatalysis, UV photolysis and TiO2 adsorption and that of the control were 92.8%, 32.5%, 18.0% and 16.6%, respectively. TiO2 photocatalytic pretreatment accelerated the biohydrogen production from 10-fold diluted WAS. The bioreactors containing UV photolysis and TiO2 adsorption pretreated WASs and the control reactor require 0.5-d, 0.9-d and 0.7-d start-up period for biohydrogen production, respectively. While the bioreactor containing TiO2 photocatalysis pretreated WAS obtained a hydrogen yield of 0.5 mL-H2/g-VS merely after 0.5-d mesophilic fermentation. The cumulative biohydrogen production from TiO2 photocatalysis pretreated WAS during 4-d mesophilic fermentation reached 11.7 mL-H2/g-VS, which was 1.2 times higher than that from the control. TiO2 photocatalytic pretreatment enhanced the biohydrogen production from WAS via accelerating the hydrolysis of its macromolecular components to smaller molecule weight hydrolysates.

Efficient Electrochemical Removal of Ammonia with Various Cathodes and Ti/RuO₂-Pt Anode

Electrochemical oxidation of ammonia was studied with an objective to enhance the selectivity of ammonia to nitrogen gas and to remove the by-products in an undivided electrochemical cell, in which various cathodes and Ti/RuO 2-Pt anode were assembled. In the present study, anodic oxidation of ammonia and cathodic reduction of by-products were achieved, especially with Cu/Zn as cathode. In the presence of 1.0 g/L NaCl the ammonia-N decreased from 100.0 to 0 after 120 min electrolysis at current density of 30 mA/cm2, and no nitrite was detected in the treated solution. The lowest amount of nitrate was formed with Cu/Zn as cathode during electrolysis due to its high reduction ability. Initial pH range from 7 and 9 and uncontrolled temperature were favorable for electrochemical ammonia oxidation and the ammonia oxidation rates with Cu/Zn cathode was higher than that with Ti and Fe cathode. The reduction rate increased with increasing current density in the range of 5 - 50 mA/cm2. As ammonia could be completely removed by the simultaneous oxidation and reduction in this study, it is suitable for deep treatment of ammonia polluted water.

Electrochemical Degradation of Chlorsulfuron Herbicide from Water Solution Using Ti/IrO₂-Pt Anode

Chlorsulfuron (ChS) which is a nonbiodegradable herbicide was effectively removed using an electrochemical method at the Ti/IrO2-Pt anode. The influences of current density, initial ChS concentration, initial solution pH and different NaCl dosages on electrochemical degradation of ChS were investigated. HOCl formed during electrolysis and quickly generated .OH radicals would likely play an important role in the electrochemical degradation of ChS with the presence of NaCl. At current density of 20 mA?cm–2, ChS concentration decreased from 1 mg.L–1 to 0 mg.L–1 after 10 min electrolysis with 0.2 g?L–1 NaCl dosage. It was found that the ChS removal rate increased with increasing current density and the ChS degradation was similar at different initial pH values, which means that Ti/IrO2-Pt anode can be used in a wide pH range. The electrochemical performance of Ti/IrO2-Pt anode for degradation of ChS will not decrease after serviced for a long time. These results reveal that an electrochemical approach would be a novel treatment method for effective and rapid degradation of ChS herbicide from aqueous solution.

Influence of viscosity on chondrogenic differentiation of mesenchymal stem cells during 3D culture in viscous gelatin solution-embedded hydrogels

Differentiation of human bone marrow-derived mesenchymal stem cells(hMSCs)is regulated by a variety of cues of their surrounding microenvironments.In particular,mechanical properties of cell culture matrices have been recently disclosed to play a pivotal role in stem cell differentiation.However,it remains elusive how viscosity affects the chondrogenic differentiation of hMSCs during three-dimensional(3 D)culture.In this study,a 3 D culture system that was established by embedding viscous gelatin solution in chemically cross-linked gelatin hydrogels was used for 3 D culture of hMSCs in gelatin solutions with different viscosities.The influence of solution viscosity on chondrogenic differentiation of hMSCs was investigated.Viscous gelatin solutions promoted cell proliferation in the order of low,middle and high viscosity while elastic hydrogels restricted cell proliferation.High viscosity gelatin solution led to increased production of the cartilaginous matrix.Under the synergistic stimulation of chondrogenic induction factors,high viscosity was beneficial for the chondrogenic differentiation of hMSCs.The results suggested the role of viscosity should be considered as one of the dominant mechanical cues affecting stem cell differentiation.