Phase separation in solvent extraction of cobalt from acidic sulfate solution using synergistic mixture containing dinonylnaphthalene sulfonic acid and 2-ethylhexyl 4-pyridinecarboxylate ester

Phase separation rate is a critical character in determining the usefulness of a solvent extraction system in hydrometallurgy. A survey of the synergistic mixture containing dinonylnaphthalene sulfonic acid (HDNNS) and 2-ethylhexly 4-pyridinecarboxylate ester (4PC) for the extraction of cobalt from acidic single metal sulfate solution was carried out to suggest how the physicochemical properties and the morphology of the reverse micelles in the loaded organic phase affect the phase separation. The results show that effective parameters affecting the phase separation are the viscosity and the excess water uptake of the loaded organic phase. It is obvious that the specific settling rate (SSR) decreases with the apparent increase of these two parameters. The measurement of small angle X-ray scattering (SAXS) proves that the morphology of the reversed micelles in the loaded organic phase changes evidently with the change of the specific settling rate (SSR).

Phase behavior of heavy oil-solvent mixture systems under reservoir conditions

A novel experimental procedure was proposed to investigate the phase behavior of a solvent mixture(SM)(64 mol%CH4,8 mol%CO2,and 28 mol%C3 H8)with heavy oil.Then,a theoretical methodology was employed to estimate the phase behavior of the heavy oil-solvent mixture(HO-SM)systems with various mole fractions of SM.The experimental results show that as the mole fraction of SM increases,the saturation pressures and swelling factors of the HO-SM systems considerably increase,and the viscosities and densities of the HO-SM systems decrease.The heavy oil is upgraded in situ via asphaltene precipitation and SM dissolution.Therefore,the solvent-enriched oil phase at the top layer of reservoirs can easily be produced from the reservoir.The aforementioned results indicate that the SM has promising application potential for enhanced heavy oil recovery via solvent-based processes.The theoretical methodology can accurately predict the saturation pressures,swelling factors,and densities of HO-SM systems with various mole fractions of SM,with average error percentages of1.77%for saturation pressures,0.07%for swelling factors,and 0.07%for densities.

Programming molecular switches in water and ethanol via thermo-sensitive polymers for phase control in energetic crystals

The practical application of energetic materials, particularly 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20), is frequently impeded by phase transition challenges. In this study, we propose a novel strategy to enhance the stability of CL-20 by employing a thermo-sensitive polymer,poly(N-isopropylacrylamide)(PNIPAM), to modulate its phase transitions. Our approach involves the use of an in-situ polymerized polydopamine(PDA) shell as a platform for surface grafting through atom transfer radical polymerization, yielding a core-shell structured CL-20@PDA-PNIPAM. Through comprehensive characterization, the successful grafting of PNIPAM is confirmed, significantly enhanced the phase stability of CL-20. Notably, our core-shell structure exhibits a 13℃ increase in phase transition temperature compared to raw CL-20, thereby delaying the ε→a phase transition by over 80 min under combined thermal and solvent conditions. The enhanced stability is attributed to the hydrophobic nature of PNIPAM above its low critical solution temperature in water, which effectively shields the CL-20 crystal. These findings provide new insights into enhancing the stability and safety of energetic materials in complex environments, highlighting the potential of our molecular switch mechanism.

Effect of two-step solid solution on microstructure andδphase precipitation of Inconel 718 alloy

Inconel 718 is the most popular nickel-based superalloy and is extensively used in aerospace,automotive,and energy indus-tries owing to its extraordinary thermomechanical properties.The effects of different two-step solid solution treatments on microstructure andδphase precipitation of Inconel 718 alloy were studied,and the transformation mechanism fromγ″metastable phase toδphase was clarified.The precipitates were statistically analyzed by X-ray diffractometry.The results show that theδphase content firstly increased,and then decreased with the temperature of the second-step solid solution.The changes in microstructure andδphase were studied by scanning electron microscopy and transmission electron microscopy.An intragranularδphase formed in Inconel 718 alloy at the second-[100]_(δ)[011]γ step solid solution temperature of 925℃,and its orientation relationship withγmatrix was determined as//and(010)_(δ)//(111)γ.Furthermore,the Vickers hardness of different heat treatment samples was measured,and the sample treated by second-step solid solution at 1010℃ reached the maximum hardness of HV 446.84.

A CO_(2)-controllable phase change absorbent solvent used to waste recycling of dining lampblack

Dining lampblack as a source of atmospheric pollution,urban residents had to spend a lot of economic costs all year round to solve its impact.However,traditional treatment methods often carry the risk of secondary pollution.The use of phase change absorption solvent(PCAS)controlled by CO_(2)can effectively absorb the oily components in dining lampblack,and smoothly avoid the generation of secondary pollutants and squandering of resources.The reversibility of PCASs under CO_(2)control was explained by pH changes and macroscopic visualizations.The absorption effects of favorable absorbents and PCASs on dining lampblack were compared and analyzed.The fatty acid(FA)in the oil absorption mixture was desorbed by interacting with D230.The results of GC/MS analysis on the oil components separated by desorption showed that the desorption of PCASs was effective for these refractory oil components.FAs can be enriched and applied to the subsequent dining lampblack treatment link to realize the waste recycling.In addition,the absorption and desorption of oily components by PCASs were combined with the CO_(2)-controlled phase transformation of PCASs itself to achieve the absorption circulation of treating dining lampblack by using PCASs.

Simultaneous Determination of Four Estrogens in Compost Based on Ultrasonic Solvent Extraction, Solid-Phase Extraction Clean-Up and Analysis by UHPLC-MS/MS

A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost samples from the biodegradation of biological infectious hazardous wastes. Ultrasonic solvent extraction, using methanol as extraction solvent, coupled with SPE clean-up, using cartridges HLB 60 mg - 6 ml Supelco® and acetonitrile for reconstitution of eluents, was used for the simultaneous extraction of the four estrogens. Mean recoveries in the range of 98% - 107% were obtained. All compounds were separated in a single gradient run by UHPLC KinetexTM 2.6 μm XB-C18 100 ÅLC (50 × 4.6 mm) column. Analytes were detected via multiple reaction monitoring (MRM) using an AB SCIEX API-5000TM triple quadrupole (Applied Biosystems/MDS SCIEX) with electrospray ionization in negative mode. Isocratic mobile phase of Water:ACN (50:50) resulted to be the optimum. Limits of detection and quantification were on the order of 0.66 ng·g-1 and 2 ng·g-1 for all the estrogens. These limits were lower than most of the values reported in the literature for similar matrices. Suitable level of linearity, good repeatability and reproducibility with coefficients of variation is lower than 11.7%, 6.8% and 8.3%, respectively.

Efficient Solvent- and Catalyst-Free Syntheses of Imine Derivatives Applying the Pressure Reduction Technique: Remarkable Change of the Reaction Rate with the Phase Transition

Because imines could be used as convenient starting materials in various fields, the development of an easy synthetic method of imine was strongly desired. In response to this demand, we thought that it would be an effective synthesis method if an aldehyde and an amine could be reacted to give an imine in good yield under solvent- and catalyst-free conditions. In fact, we tried the reaction of benzaldehyde with various amines under solvent- and catalyst-free conditions followed by removal of water that was produced in the reaction system by a vacuum pump, and desired imines could be obtained in good yields. Observation of this reaction using a nuclear magnetic resonance spectrometer revealed that the reaction rate was extremely fast at the initial stage but slowed over time. However, the reaction of benzaldehyde with aniline differed greatly, and the reaction rate dramatically improved in 47 - 48 minutes after the start of the reaction. At this time, we found that the reaction system underwent a phase transition from the liquid phase to the solid phase.

Phase evolution of plasma sprayed Al_2O_3-13%TiO_2 coatings derived from nanocrystalline powders

Commercial nanosized alumina and titania particles were selected as raw materials to prepare the blended slurry with composition of A1203-13%TiO2 （mass fraction）, which were reconstituted into micrometer-sized granules by spray drying, subsequently sintering at different temperatures to form nanostructured feedstock for thermal spraying, and then A1203-13%TiO2 nanocoatings were deposited by plasma spraying. The evolution of morphology, microstructure, and phase transformation of the agglomerated powder and as-sprayed coatings were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results show that A1203 retains the same a phase as the raw material during sintering, while TiO2 changes from anatase to futile. During plasma spraying, some a-A1203 phases solidify to form metastable y-A1203, and the volume fraction of a-A1203 decreases as CPSP increases. However, peaks of the TiO2 phase are not observed from the as-sprayed coatings except for the coatings sprayed at the lower CPSP. As the CPSP increases, nanostructured TiO2 is dissolved easily in y-A1203 or z-A1203＇TiO2 phase. After heat treatment, y-A1203 in the coatings transforms to a-A1203, and rutile is precipitated.

Synthesis and Solid Phase Extraction Performance Study of NNAL-specific Molecularly Imprinted Polymers Using Dummy Templates

Dummy molecularly imprinted polymers （DMIPs） for 4-（methylnitrosamino）-1-（3-pyridyl）-1-butanol （NNAL） were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-（acetymethylamino）-1-（3-pyridyl）-butanol, 4- （methylamino）-1-（3-pyridyl）-1-butanol, and 1-（3-pyridyl）-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy （XPS） and Fourier transform infrared spectroscopy （FT-IR）. Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-（acetymethylamino）-1-（3-pyridyl）-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction （DMISPE） was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.

Influences of solid particles on the formation of the third phase crud during solvent extraction

The influences of solid particles in leach solution on the formation of the third phase crud during solvent extraction of copper were studied. Analyzed from the point of view of pH value and surface tension, the study results showed that the solid particle is one of the most important contributors for the formation of the third phase crud. During solvent extraction, if the pH value was greater than 2.30, the number of solid particles in the mother solution increased, in which case the possibility of forming the third phase crud could also increase, and the interface tension value might grow in pace with the quantity of the third phase crud.

The effect of temperature on phase equilibria of polyethylene glycol(PEG8000)-K_(2)SO_(4)-H_(2)O at T=(288.15,298.15,308.15)K

The phase behavior of potassium sulfate(K_(2)SO_(4))in polyethylene glycol with molecular weight 8000(PEG8000)andwater(H_(2)O)mixed solvent at 288.15,298.15,and 308.15 Kwere determined.According to the results,when the temperature are 288.15 and 298.15 K,there is only a solid-liquid phase equilibrium relationship in the system,and the phase diagrams are both divided into three parts which respectively are the regions of unsaturated homogeneous liquid(L),one liquid and one solid K_(2)SO_(4)(L+S)and one liquid and twosolids K_(2)SO_(4) and PEG8000(L+2S).The solubility of K_(2)SO_(4) in PEG8000-H_(2)O mixed solvent decreased with the addition of the PEG8000 in the solution.Comparing the diagrams of 288.15 and 298.15 K,the sizes of regions of(L)and(L+S)increased and that of(L+2S)decreased with the increase of temperature.While at 308.15 K,solid-liquid and liquid-liquid equilibrium coexist,and there are six parts in the complete phase diagram at 308.15 K,adding the areas of one liquid and one solid K_(2)SO_(4)(L+S),two liquids(2 L),two liquids and one solid K_(2)SO_(4)(2 L+S).The equations developed by Merchuk,Hu,and Jayapalwere used to fit the binodal curves data of the systemat 308.15 K,meanwhile,the experimental tie-line data of the system at 308.15 K were correlated by Othmer-Tobias equation and Bancroft equation.

Prediction of dispersed phase holdup in pulsed disc and doughnut solvent extraction columns under different mass transfer conditions

Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns （PDDC） have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDC has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDC were used to refit constants for the correlation presented by Kumar and Hartland lind. Eng. Chem. Res.,27 （1988）,131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDC （i.e. the plate spacing）, the unified cor- relation for holdup proposed by Kumar and Hartland based on data from eight different types of columns [Ind. Eng. Chem. Res.,34 （1995） 3925-3940] was refitted to the PDDC data. New constants have been presented for each hold- up correlation for a PDDC based on regression analysis using published holdup data from PDDCs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer.

An efficient preparation of porous polymeric microspheres by solvent evaporation in foam phase

This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase,in which phase separation between polymer and porogen occurs in foam phase instead of that in water phase by using the traditional solvent eva poration method.The method provides outstanding features,including being time-saving,of high-yield and able for continuous production,in which formation of porous polymeric microspheres finished within 3 min with a high production yield up to approximate 95 wt% and the process was able to be developed into a continuous process for production of porous polymeric microspheres.It was also universal to non-crosslinked polymers since the method is a development on the traditional emulsion solvent evaporation method.The new method is efficient and can be used potentially on the industrial scale for continuous production of porous polymeric microsphere s.

Modification and refinement mechanism of Mg_2Si phase in Sr-containing AZ61-0.7Si magnesium alloy

The effect of Sr on modification and refinement of the Mg 2 Si phase in an AZ61-0.7Si magnesium alloy has been investigated and analyzed.The results indicate that Sr can effectively modify and refine the Chinese-script shaped Mg2Si phase in the AZ61-0.7Si alloy.By adding 0.06wt.%-0.12wt.%Sr to AZ61-0.7Si alloy,the Mg2Si phase in the alloy can be changed from the initial coarse Chinese-script shape to fine granule and/or irregular polygonal shapes.Accordingly,the Sr-containing AZ61-0.7Si alloy exhibits higher tensile and creep properties than the AZ61-0.7Si alloy without Sr modification.The mechanism on modification and refinement of the Mg2Si phase in Sr-containing AZ61-0.7Si alloy is possibly related to the following two aspects:(1)adding Sr may form the Al4Sr phase which can serve as the heterogeneous nucleus for the Mg2Si particles and/or(2)adding Sr may lower the onset crystallizing temperature and increase the undercooling level.

Study of the Liquid Phase Volume Expansion for CO_2/Organic Solvent Systems

The supercritical antisolvent （SAS） process has been developed in recent years for the tormation of nanoand micro-particles. It is necessary to study the liquid phase volume expansion （LPVE） and find the relationships between the operating conditions and the LPVE in order to develop a practical method for determining the operation conditions and selecting an organic solvent for SAS process. The PR equation of state with vdW-1 mixing rule is used to calculate the LPVE for CO2/toluene, CO2/acetone and CO2/ethyl acetate systems, and the results show that the LPVE for each CO2/organic solvent system decreases as the temperature increases. The relationship between the LPVE and the solubility of CO2 in the liquid phase for CO2/organic solvent systems is investigated, and the results show that the LPVE is determined directly by the solubility of CO2 in the liquid phase, xCO2, and can be related to xCO2 independently. No matter what system of CO2/organic solvent is and how different the temperature is, the LPVEs have little difference as long as the solubility of CO2 in the liquid phase, xCO2, keeps constant. The lower temperature is always favorable to the SAS process. The higher the solubility of CO2 in an organic solvent under certain operation condition, the more suitable it is to the SAS process.

Asymmetric Synthesis of (-)-1-Trimethylsilyl-ethanol with Immobilized Saccharomyces Cerevisiae Cells in Water/Organic Solvent Diphasic System

Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.

Solvent extraction of copper and ammonia from ammoniacal solutions using sterically hindered β-diketone

Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper concentration,the total ammonia concentration,the initial pH in the aqueous phase,the phase ratio,and the temperature on copper extraction ratio and ammonia extraction in loaded organic phase were investigated using this sterically hindered β-diketone.Under the conditions of temperature 25℃,contact time of two phases 30 min,phase ratio 1-1,concentration of copper 3 g/L,concentration of total ammonia 3 mol/L,aqueous pH 8.43,and the concentration of β-diketone in organic phase 20%(volume fraction),ammonia in aqueous phase is much lower to be extracted by organic phase(just 14.5 mg/L),while the extraction rate of copper is 95.09%.

A Phase II Study of Antineoplastons A10 and AS2-1 in Children with High-Grade Glioma. Final Report (Protocol BT-06), and Review of Recent Trials

Standard treatment for high-grade glioma involves surgical resection followed by radiation therapy and temozolomide. Unfortunately, there are no standard treatment recommendations after recurrence and new therapies are needed for patients whose tumor recurs after first-line treatment. This single-arm, two-stage, interventional Phase II study evaluated the efficacy and safety of a combination of antineoplastons A10 and AS2-1. Nineteen patients were enrolled in the study (safety population), but fifteen patients with a median age of 9.4 years who met eligibility criteria were evaluated. The majority of subjects (12/15) were Caucasian and 8/15 (53%) were female. More than half (53%) of patients were diagnosed with glioblastoma and 33% with anaplastic astrocytoma. All patients had failed standard therapy including surgery, radiation, and chemotherapy. Antineoplastons were administered intravenously every four hours (median dose of A10 6.9 g/kg/d and AS2-1 0.30 g/kg/d) until objective response was documented and thereafter for a further 8 months. Clinical evaluations were performed every 8 weeks. All patients enrolled in the study were included in the safety analysis but only patients fulfilling the inclusion criteria were included in the efficacy evaluation. The duration of treatment with antineoplastons ranged from 2 weeks to 120 weeks. A complete response was documented in 2/15 (13%), partial response in 2/15 (13%), stable disease in 3/15 (20%). Progression-free survival at six months was 47% and overall survival (OS) at one year was 33.3%. One patient (6.7%) survived 10 years from treatment start. A small group of patients suffered reversible Grade 3 and 4 toxicities including hypernatremia 2/19 (11%) and decrease of neutrophils 1/19 (5%). There were no chronic toxicities. There was improvement of quality of life in patients who had objective response. It is concluded that antineoplastons show efficacy with an acceptable profile in this cohort of patients with recurrent high-grade glioma.

A Phase II Study of Antineoplastons A10 and AS2-1 in Adult Patients with Recurrent Glioblastoma Multiforme: Final Report (Protocol BT-21)

Treatment of recurrent glioblastoma multiforme (RGBM) creates one of the most difficult challenges to neuro-oncology. The purpose of this study is to evaluate the outcome of adults with high-grade glioma with special attention to RGBM patients treated with Antineoplastons (ANP) A10 and AS2-1 injections. The study was conducted according to Protocol BT-21, which accrued patients who failed standard radiation therapy (RT) and chemotherapy. There were 40 candidates registered in the study. Among the intent-to-treat (ITT) population, there were 30 cases of RGBM that progressed during and after prior treatment, 4 patients with anaplastic astrocytoma (AA), 1 with anaplastic mixed glioma (AMG), and 5 with persistent GBM. The aim of this paper is to evaluate the responses, survival and toxicity of all 40 patients, the efficacy in 30 patients with RGBM, and in 24 patients with RGBM who received at least 28 days of ANP (ERGBM). All RGBM patients were treated before with RT and chemotherapy, except one patient who only had surgery (patient refused radiation). In this group, 63% had one recurrence, 30% had two recurrences, and 7% had three recurrences. The median duration of ANP and ITT was 12 weeks and the median dosage of ANP A10 was 6.52 g/kg/d and ANP AS2-1 was 0.23 g/kg/d. Responses were assessed by gadolinium-enhanced magnetic resonance imaging (MRI) repeated every eight weeks. In the ITT population, objective responses (ORs) were determined in 10% of cases (complete response—CR, and partial response—PR in 5% each). Progression-free survival (PFS) in ITT at six months was 17.5%. Overall survival (OS) was 28.3% at one year, 2.6% at two years, five and ten years. In the RGBM population, objective responses (ORs) were determined in 13.3% of cases (CR and PR in 6.7% each). PFS in RGBM at six months was 16.7%. OS was 34.7% at one year, 3.47% at two years, five?and ten years. In the ERGBM population, ORs were determined in 16.7% of cases (CR and PR in?8.3% each). PFS in ERGBM at six months was 20.8%, OS was 39.3% at one year, 4.4% at two years, five and ten years. The treatment was well-tolerated with reversible Grades 3 and 4 toxicity in 17.5% of patients (7 patients who experienced multiple toxicities) and no chronic toxicity. In conclusion, the study reached efficacy endpoint. ANP is well-tolerated and compares favorably to the current treatment for RGBM.

Thermodynamic modeling and phase diagram prediction of salt lake brine systemsⅡ.Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems

It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(Δg_(IJ),Δh_(IJ),and ΔC_(p,IJ))associated with the contributions of Gibbs energy,enthalpy,and heat capacity to the binary interaction parameters,i.e.the temperature coefficients of eNRTL parameters formulated with a Gibbs Helmholtz expression,are determined via multi-objective optimization method.The solid constantsΔ_(f)G_(k)°^((298.15))andΔ_(f)H_(k)°^((298.15))of11 solid species occurred in the quaternary system are rebuilt from multi-temperature solubilities.The modeling results show the accurate representation of(1)solution properties and binary phase diagram at temperature ranges from eutectic points to 643 K;(2)isothermal phase diagrams for Li_(2)SO_(4)-Na_(2)SO_(4)-H_(2)O,Li_(2)SO_(4)-K_(2)SO_(4)-H_(2)O and Na_(2)SO_(4)-K_(2)SO_(4)-H_(2)O ternary systems.The predicted results of complete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data.