Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium

The extraction of Nd^3＋ and Sm^3＋, including the extraction and stripping capability as well as the separation effect of Nd^3＋ or Sm^3＋, from a sulfuric acid medium, by mixtures of di-（2-ethylhexyl） phosphoric acid （HDEHP, H2A2（0）） and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester （HEH/EHP, H2L2（0）） were studied. The distribution ratios and synergistic coefficients of Nd^3＋ and Sm^3＋ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3＋ or Nd^3＋. The chemical compositions of the extracted complex were determined as Nd.（HA2）2-HL2 and Sm.（HA2）2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.

Urine Metabonomic Analysis of Interventions Effect of Soy Isoflavones on Rats Exposed to Di-(2-ethylhexyl) Phthalate

Objective Di-(2-ethylhexyl) phthalate(DEHP) is a ubiquitous environmental contaminant.As an endocrine disruptor,it seriously threatens human health and ecological environmental safety.This study examines the impact of intervention with soybean isoflavones(SIF) on DEHP-induced toxicity using a metabonomics approach.Methods Rats were randomly divided into control(H),SIF-treated(A,86 mg/kg body weight),DEHP-treated(B,68 mg/kg),and SIF plus DEHP-treated(D) groups.Rats were given SIF and DEHP daily through diet and gavage,respectively.After 30 d of treatment,rat urine was tested using UPLC/MS with multivariate analysis.Metabolic changes were also evaluated using biochemical assays.Results Metabolomics analyses revealed that p-cresol glucuronide,methyl hippuric acid,N1-methyl-2-pyridone-5-carboxamide,lysophosphatidycholine [18:2(9 Z,12 Z)] {lyso PC [18:2(9 Z,12 Z)]},lyso PC(16:0),xanthosine,undecanedioic acid,and N6-acetyl-l-lysine were present at significantly different levels in control and treatment groups.Conclusion SIF supplementation partially protects rats from DEHP-induced metabolic abnormalities by regulating fatty acid metabolism,antioxidant defense system,amino acid metabolism,and is also involved in the protection of mitochondria.

Adsorption by Liquid-Liquid Extraction of Hg(II) from Aqueous Solutions Using the 2-Butyl-imidazolium Di-(2-ethylhexyl) Phosphate as Ionic Liquid

In this work, a novel room temperature ionic liquid (2-butyl-imidazolium di-(2-ethylhexyl) phosphate) ([C4mim] [D2EHPA]) was synthesized and tested as extractant in the mercury(II) liquid-liquid extraction. The effects of parameters such as aqueous to organic phase’s volume ratio, metal concentration IL concentration, pH levels, ionic strength, and temperature were reported. For the extraction of metal, [C4mim]3[R.HR]3[HgCl2]org and [C4mim]3[R.HR]3 [HgClOH]org species were formed where (H2R2) was D2EHPA. In the case of ionic strength, the results showed that the addition of sodium acetate at 0.302 mmol·L?1 to the aqueous phase strongly increased the mercury extraction yield (R = 100%). The extracted species were investigated by a calculation program using CHEAQS V. L20.1 inorder to determine the relation between the percentages of the extracted species and the extraction yield. The results showed that the extracted species in the best conditions were HgCl2 and HgClOH with respective percentages 80.66% and 18.29%.

N-acetylcysteine and zinc sulphate abate di-2-ethylhexyl phthalate-mediated reproductive dysfunction in rats:Focus on oxidative and sex hormone receptors mechanisms

Objective:To investigate the potential of N-acetylcysteine(NAC)and zinc sulphate(ZnSO_(4))in mitigating reproductive dysfunction caused by di-2-ethylhexyl phthalate(DEHP)in rats and to understand the underlying mechanisms,specifically oxidative stress and sex hormone receptor activity.Methods:Thirty-five male Wistar rats were randomly divided into five equal groups(n=7 per group).Group 1 was administered 0.5 mL of distilled water and served as the control group.Group 2 was given only DEHP(750 mg/kg/day),while group 3,4 and 5 were given DEHP(750 mg/kg/day)plus NAC(100 mg/kg/day),DEHP(750 mg/kg/day)plus ZnSO_(4)(0.5 mg/kg/day),and DEHP(750 mg/kg/day)plus NAC(100 mg/kg/day)as well as ZnSO_(4)(0.5 mg/kg/day),respectively.All treatments lasted for 21 days.Samples were obtained after the rats were sacrificed,and hormones levels in the serum and markers of oxidative stress in the testicles were analyzed using the enzyme-linked immunosorbent assay.The amount of androgen receptors in the testicles was determined by immunohistochemistry,and the susceptibility of testosterone and DEHP to bind to androgen receptor and 5α-reductase was determined by molecular docking studies.Results:DEHP decreased reproductive hormones,testicular antioxidant enzymes,increased malondialdehyde levels,and negatively impacted histology of the pituitary and testes.NAC or ZnSO_(4) treatment showed a marked improvement in testicular antioxidant status and hormone levels,as well as a positive effect on the histology of the pituitary and testes.The combination of both treatments appeared to be more effective.The affinity of DEHP to bind to androgen receptors may lead to disruption of androgen receptor signaling,which can further result in dysfunction of hormones related to androgen.However,NAC is more likely to form stronger binding interactions with follicle stimulating hormone and luteinizing hormone receptors,as well as gonadotropin-releasing hormone receptors,when compared to DEHP.Conclusions:The possibility that NAC and ZnSO_(4) could downregulate DEHP-induced sex hormone changes is suggested by their potential to reduce toxicity.

Solid-phase extraction and separation of indium with P_(2)O_(4)-UiO-66-MOFs (di-2-ethylhexyl phosphoric acid-UiO-66-metal-organic frameworks)

Compared with the traditional liquid–liquid extraction method,solid-phase extraction agents are of great significance for the recovery of indium metal due to their convenience,free of organic solvents,and fully exposed activity.In this study,P_(2)O_(4)(di-2-ethylhexyl phosphoric acid)was chemically modified by using UiO-66 to form the solid-phase extraction agent P_(2)O_(4)-UiO-66-MOFs(di-2-ethylhexyl phosphoric acid-UiO-66-metal-organic frameworks)to adsorb In(Ⅲ).The results show that the Zr of UiO-66 bonds with the P-OH of P_(2)O_(4) to form a composite P_(2)O_(4)-UiO-66-MOF,which was confirmed by X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FT-IR).The adsorption process of indium on P_(2)O_(4)-UiO-66-MOFs followed pseudo first-order kinetics,and the adsorption isotherms fit the Langmuir adsorption isotherm model.The adsorption capabilities can reach 192.8 mg/g.After five consecutive cycles of adsorption-desorption-regeneration,the indium adsorption capacity by P_(2)O_(4)-UiO-66-MOFs remained above 99%.The adsorption mechanism analysis showed that the P=O and P-OH of P_(2)O_(4) molecules coated on the surface of P_(2)O_(4)-UiO-66-MOFs participated in the adsorption reaction of indium.In this paper,the extractant P_(2)O_(4) was modified into solid P_(2)O_(4)-UiO-66-MOFs for the first time.This work provides a new idea for the development of solid-phase extractants for the recovery of indium.

Plastic Additives Decrease Agrin-Induced Acetylcholine Receptor Clusters and Myotube Formation in C2C12 Skeletal Muscle Cell Culture

Common additives in plastics such as bisphenol A (BPA) or phthalates like di-(2-ethylhexyl) phthalate (DEHP) are environmental estrogens that have been shown to be endocrine disruptors in some experimental animal models. This project used the C2C12 cell culture model to examine how exposure to BPA or DEHP affects two aspects of skeletal muscle development, the fusion of myoblasts into myotubes and agrin-induced clustering of acetylcholine receptors (AChRs). During myotube formation AChRs cluster spontaneously. Treatment with motor neuron derived agrin increases the frequency of AChR clusters through an agrin signaling pathway that also clusters other postsynaptic components of the neuromuscular synapse. For this project C2C12 cells were exposed to BPA or DEHP while myoblasts fused into myotubes. After exposure to 10 μM BPA or 100 μM DEHP the frequency of agrin-induced AChR clusters decreased. In addition, myotube formation decreased as a higher percentage of nuclei remained in myoblasts. Furthermore, BPA or DEHP reduced the amount of the myogenic regulatory factor myogenin. This suggests that BPA and DEHP decrease AChR clustering by reducing myogenin. Moreover, plastic additives like BPA and DEHP may pose a risk for skeletal muscle development in humans.

Selective Separation of Light and Heavy Rare Earth Elements from the Pregnant Leach Solution of Apatite Ore with D2EHPA

Different separation techniques such as solvent extraction, ion exchange, and precipitation are often used for recovery of rare earth elements (REEs) from pregnant leach solutions obtained from acid leaching. Solvent extraction is generally accepted as the most appropriate commercial technology for separating REEs due to the need to be able to handle larger volumes of diluted pregnant solutions. This study focused on the development of selective separation of light and heavy REEs from the pregnant leach solution obtained from leaching of apatite ore in 1 M sulfuric acid (H2SO4) using solvent extraction. Three different commercial organophosphorus extractants (di-(2-ethylhexyl) phosphoric acid (D2EHPA), 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC88A) and tributyl phosphate (TBP)), and the influences of experimental parameters such as extractant concentration, organic/aqueous phase ratio, diluent type, pH, extraction time and stripping agent concentration were examined. Results showed that light REEs (LREEs) and heavy REEs (HREEs) in the pregnant leach solution were selectively separated with D2EHPA via a two-stage extraction process. In the first-stage of solvent extraction, >90% of (0.05 g/L) HREEs was extracted with 1.8 M D2EHPA in kerosene while the vast majority (>95%) of LREEs was remained in raffinate. In the second-stage, >93% (1.01 g/L) of LREEs was extracted from the raffinate with 1.8 M D2EHPA dissolved in kerosene at pH 1.6. HREEs (>95%) and LREEs (>90%) loaded with D2EHPA after the first and second-stage of extraction were stripped by 4 M H2SO4 and 1 M H2SO4 solutions, respectively. Distribution of middle rare earth elements (MREEs) was discussed through the extraction processes in this study.

Primary neuronal-astrocytic co-culture platform for neurotoxicity assessment of di-(2-ethylhexyl) phthalate

Plastics such as polyvinyl chlorides （PVC） are widely used in many indoor constructed environments; however, their unbound chemicals, such as di-（2-ethylhexyl） phthalates （DEHP）, can leach into the surrounding environment. This study focused on DEHP＇s effect on the central nervous system by determining the precise DEHP content in mice brain tissue after exposure to the chemical, to evaluate the specific exposure range. Primary neuronal-astrocyte co-culture systems were used as in vitro models for chemical hazard identification of DEHP. Oxidative stress was hypothesized as a probable mechanism involved, and therefore the total reactive oxygen species （ROS） concentration was determined as a biomarker of oxidative stress. In addition, NeuriteTracer, a neurite tracing plugin with ImageJ, was used to develop an assay for neurotoxicity to provide quantitative measurements of neurological parameters, such as neuronal number, neuron count and neurite length, all of which could indicate neurotoxic effects. The results showed that with 1 nmol/L DEHP exposure, there was a significant increase in ROS concentrations, indicating that the neuronal-astrocyte cultures were injured due to exposure to DEHP. In response, astrocyte proliferation （gliosis） was initiated, serving as a mechanism to maintain a homeostatic environment for neurons and protect neurons from toxic chemicals. There is a need to assess the cumulative effects of DEHP in animals to evaluate the possible uotake and effects on the human neuronal system from exoosure to DEHP in the indoor environment.

Reference gene validation for quantification of gene expression during final oocyte maturation induced by diethylstilbestrol and di-(2-ethylhexyl)-phthalate in common carp

Final oocyte maturation is the key step to successful spawning and fertilization.Quantitative real-time PCR（q PCR） is the technique of election to quantify the abundance of functional genes in such study. Reference gene is essential for correct interpretation of q PCR data. However, an ideal universal reference gene that is stable under all experimental circumstances has not been described. Researchers should validate their reference genes while performing q PCR analysis. The expression of 6 candidate reference genes： 18 s r RNA,28 s r RNA, Cathepsin Z, Elongation factor 1-α, Glyceraldehyde-3-phosphate dehydrogenase andβ-actin were investigated during final oocyte maturation induced by different compounds（DES and DEHP） in common carp（Cyprinus carpio）. Four softwares（Bestkeeper, ge Norm,Norm Finder and Ref Finder） were used to screen the most stable gene in order to evaluate their expression stability. The results revealed that EF1α was highly stable expressed when final oocyte maturation was induced by DES, while gapdh was the most stable gene when final oocyte maturation was induced by DEHP. Stable expressed reference gene selection is critical for all q PCR analysis to get accurate target gene m RNA expression information.

Mass Transfer of Copper（Ⅱ） in Hollow Fiber Renewal Liquid Membrane with Different Carriers

The extraction ability of organophosphorus extractant D2EHPA(di-2-ethylhexyl phosphoric acid) and hydroximic extractant Lix984N are investigated by the extraction equilibrium experiments.Effects of carrier concen-tration and organic/aqueous volume ratio on the mass transfer of hollow fiber renewal liquid membrane(HFRLM) are studied.Results show that,in the extracting process,kerosene and n-heptane are more suitable than methyl-isobutyl ketone,butylacetate and benzene as the diluents of D2EHPA or Lix984N.The favorable feed pH is 4.4 for D2EHPA and 2.6 for Lix984N.The mass transfer flux of HFRLM increases with carrier concentration and finally reaches a plateau.The mass transfer flux and the overall transfer coefficient increase with the organic/aqueous volume ratio,reach the maximum and then decrease.

Interaction Between DEHP and Particulate in a Eutrophic Lake

Characteristics of interaction between di-2-ethylhexyl phthalate(DEHP) and particulate in a eutrophic lake were studied in this paper. DEHP concentrations ranged from 89.9 to 247 μg/L with an average value of 146 μg/L in subsurface water (SSW) samples, and from 82.0 to 390 μg/L with an average value of 211 μg/L in water surface microlayer (SM) samples. The results indicate that there was only a weak correlation between the DEHP concentrations and suspended particulate material(SPM) concentrations in both SSW and SM, while the significant correlation between DEHP concentrations and chlorophyll a concentrations was found, which suggestes that DEHP was principally bound to phytoplankton in the eutrophic lake. Correlation between DEHP concentrations and total phosphor (TP) concentrations was also found in this investigation.Enrichment factors (EF) of DEHP in SM were in the range of 0.85 to 2.12 with an average value of 1.35. DEHP EFs were significantly related to the enrichment of chlorophyll a in SM. The results suggest that the enrichment of DEHP in SM of this eutrophic lake was mainly due to DEHP accumulation in phytoplankton and was controlled by distribution of phytoplankton between SM and SSW.

Study on the Separation of Rare Earths with the Method of H(DEHP)-Extraction Chromatography

Separation of rare earths was investigated by extraction chromatography where H(DEHP)was used as a stationary phase,while HCl and H_2SO_4 solutions as a mobile phase.The average separation fac- tors of rare earths,β_(HCl) and β_(H_2SO_4),are 3.79 and 4.57.respectively.The β_(La)^(Ce) in HCl and H_2SO_4 systems are as high as 28.5 and 26.3,respectively.The elution acidity in the study can be down to one tenth and one four- teenth of that in HEH(EHP)system.

A microextraction approach for rapid extraction and separation of Mn(Ⅱ) and Co(Ⅱ) using saponified D2EHPA system

In this paper,we proposed a microextraction approach for the extraction and separation of Mn(Ⅱ)and Co(Ⅱ)from sulfate solution simulating leachate of spent lithium-ion battery cathode materials using saponified di-(2-ethylhexyl)phosphoric acid system.The effects of the following operational variables were investigated:equilibrium pH,tri-«-butyl phosphate concentration,saponification rate,two-phase ratio and residence time.The results showcased that the microextractor can reach the extraction equilibrium within 20 s,thereby greatly reducing necessary extraction time comparing to that of conventional processes.The volumetric mass transfer coefficient showed 8-21 times larger than that of batch device.With the help of microextractor,95%of Mn(Ⅱ)was extracted with a single theoretical stage at a chosen two-phase ratio of 3:1,and the separation factor β_(Mn/Co) was as large as 65.5.In the subsequent stripping step,more than 99%of manganese from loaded phase was easily stripped under optimal conditions.The microextraction approach greatly enhances the mass transfer while enabling a continuous and controllable extraction process within a simple structure design.When extracting spent electrode material with microextractors,the comprehensive recovery of mangenese can reach 96%.The microextraction approach has a good applicability in the spent lithium-ion battery cathode materials recycling at both bench and industrial scales.

Theoretical studies on the complexation of Eu(Ⅲ) and Am(Ⅲ) with HDEHP： structure, bonding nature and stability

Separation of trivalent lanthanides （Ln（Ⅲ）） and actinides （An（Ⅲ）） is a key issue in the advanced spent nuclear fuel repro- cessing. In the well-known trivalent actinide lanthanide separation by phosphorus reagent extraction from aqueous komplexes （TALSPEAK） process, the organophosphorus ligand HDEHP （di-（2-ethylhexyl） phosphoric acid） has been used as an efficient reagent for the partitioning of Ln（Ⅲ） from An（Ⅲ） with the combination of a holdback reagent in aqueous lactate buffer solu- tion. In this work, the structural and electronic properties of Eu3＋ and Am3＋ complexes with HDEHP in nitric acid solution have been systematically explored by using scalar-relativistic density functional theory （DFT）. It was found that HDEHP can coordinate with M（Ⅲ） （M=Eu, Am） cations in the form of hydrogen-bonded dimers HL2 （L=DEHP）, and the metal ions pre- fer to coordinate with the phosphoryl oxygen atom of the ligand. For all the extraction complexes, the metal-ligand bonds are mainly ionic in nature. Although Eu（Ⅲ） complexes have higher interaction energies, the HL2- dimer shows comparable affini- ty for Eu（Ⅲ） and Am（Ⅲ） according to thermodynamic analysis, nonahydrate. It is expected that this work could provide insightful HDEHP at the molecular level. which may be attributed to the higher stabilities of Eu（Ⅲ） information on the complexation of An（Ⅲ） and Ln（Ⅲ） with