Mixture Of Di Research Articles

Indium Extraction from Sulfate Solutions with a Mixture of Di(2-Ethylhexyl)Phosphoric Acid and Octyl Alcohol

ABSTRACT In this work, solvent extraction of In(III) from sulfate solutions by using mixtures of D2EHPA with octyl alcohol and octanoic acid was investigated. The introduction of the additives into the organic phase was shown to lead to an antagonistic effect thus facilitating efficient indium stripping from the loaded organic phase. The antagonistic effect is significantly higher in the D2EHPA (HR) and octyl alcohol (HA) mixtures. The formation of stable associates between D2EHPA and HA leads to a decrease in the extraction efficiency of indium. In the presence of alcohol, almost complete stripping of indium from a D2EHPA loaded phase can be achieved to produce a strip liquor containing>33.0 g/L In. Based on the analysis of the extraction data and by using nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy of the organic phases, it was concluded that indium extraction with D2EHPA in octyl alcohol is due to the formation of the extracted compound InR3. The equilibrium constant (logK) for indium extraction with solutions of D2EHPA in octyl alcohol was found to be − 0.12 ± 0.05. Extraction systems containing D2EHPA and octyl alcohol can be used to recover indium from various industrial solutions, in particular from the solutions derived from lead-zinc production and from liquid crystal display panel wastes.

Mixtures of Di- or Triamines and Iodine as Effective Catalysts for the Formation of Organic Carbonates from Epoxides and CO2: Effect of 2,2,2-Trifluoroethanol

Mixing di- and triamines with iodine leads to the formation of cheap and efficient catalysts for the preparation of cyclic carbonates from epoxides and CO2. The activity of these catalytic systems is found to increase upon addition of 2,2,2-trifluoroethanol.

Indium Extraction from Sulfate Solutions with a Mixture of Di(2-Ethylhexyl)Phosphoric Acid and Octyl Alcohol

Indium Extraction from Sulfate Solutions with a Mixture of Di(2-Ethylhexyl)Phosphoric Acid and Octyl Alcohol

Synergetic facilitated transport of nickel via supported liquid membrane process by a mixture of Di (2-ethylhexyl) phosphoric acid and n-octanol: Kinetic permeation study and approach for a green process

This work addresses the synergistic removal of nickel from the electroplating wastewater using a supported liquid membrane (SLM) process. The supported liquid membrane formulation consisting of Di-2-ethylhexyl phosphoric acid (D2EHPA), n-octanol, kerosene, and sulfuric acid as a carrier, synergist, diluent, and stripping agent, respectively. The effects of several significant parameters namely D2EHPA, n-octanol, and sulfuric acid concentrations as well as feed and stripping phases flow rates were investigated. Results revealed that n-octanol as a synergist significantly affected the removal efficiency of nickel since it can modify the D2EHPA molecules in the membrane phase. Besides, a kinetic model for the nickel ion transport across SLM revealed that the transport resistances due to the diffusion across the membrane (Δorg), transport resistances due to the diffusion through the aqueous boundary layer (Δaq), thickness of the aqueous diffusion layer (daq), and diffusion coefficient of the nickel-carrier complex across the membrane (Dorg) were found to be 2.90 × 105 sm−1, 1.94 × 104 sm−1, 1.24 × 10−5 m and 7.20 × 10−10 m2s−1, respectively. Interestingly, an approach to a green process by incorporating palm oil as a diluent showed that it is feasible to be applied and offers a green SLM process in the future.

Solvent extraction of nickel ions from electroless nickel plating wastewater using synergistic green binary mixture of D2EHPA-octanol system

A study on the synergistic green solvent extraction of nickel ions from real electroless nickel plating wastewater using an organic phase containing a binary mixtures of Di (2-ethylhexyl) phosphoric acid (D2EHPA) and octanol in palm oil was conducted. The effects of diluent composition, synergist, carrier and stripping agent types and its concentrations were experimentally investigated and the optimum conditions were determined. Results revealed that both D2EHPA and octanol acted as a carrier and synergist, respectively. A significant synergistic effect occurred when the octanol helped destroy the dimer structure of D2EHPA for cation exchange mechanism with nickel ions, hence improving the nickel ions extraction up to 90% with the maximum distribution ratio of 8.8 under optimum condition of 0.7M D2EHPA and 15% (v/v) octanol in palm oil. Afterwards, the stripping experiment showed that nickel ions could be recovered from the loaded mixture of carrier using 1.0M nitric acid solutions. Besides, the slope analysis method showed that the nickel ions were extracted from weak acidic electroplating feed solution as nickel-D2EHPA-octanol complex and recovered as nickel nitrate complex in the stripping phase. Thus, it can be concluded that the green synergistic formulation containing binary mixtures of D2EHPA-octanol system is one of the promising approaches as well as a green and efficient separation method for nickel ions extraction from the real electroless nickel plating wastewater.

Neurological Toxicity of Individual and Mixtures of Low Dose Arsenic, Mono and Di (n-butyl) Phthalates on Sub-Chronic Exposure to Mice

The objective of this study was to evaluate the toxicity of individual and mixtures of di(n-butyl) phthalates (DBP) and their active metabolite monobutyl phthalate (MBP) and arsenic (As) on spatial cognition associated with hippocampal apoptosis in mice. Mice were exposed, individually or in combination, to DBP (50mg/kg body weight, intragastrically), MBP (50mg/kg body weight, intragastrically), and As (10mg/L, per os) for 8weeks. The Morris water maze test showed that mice exposed to DBP/MBP combined with As exhibited longer escape latencies and the lower average number of crossing the platform. The As content in the hippocampus after As exposure increased as compared to those without As exposure. In mice exposed to DBP/MBP combined with As, pathological alterations and oxidative damage to the hippocampus were found. Expression of apoptosis-related protein: Bax and caspase-3 were significantly increased in the hippocampus, while there was no significant change in expression of Bcl-2. The results suggested that DBP and MBP combined with As can induce spatial cognitive deficits through altering the expression of apoptosis-related protein and As played a critical role in cognition impairments. And the joint exposure has antagonistic effect.

Acoustical Properties of Ternary Mixtures of Di-(2ethyl- hexyl)phosphoric Acid, Benzene and m-Xylene at Different Temperatures

Ultrasonic velocity (U) and density (ρ) of the ternary mixtures of di-(2-ethylhexyl) phosphoric acid (DEHPA), benzene and m-xylene were measured at atmospheric pressure and temperatures from 298.15K to 313.15K at an interval of 5K. The experimental data have been used to calculate adiabatic compressibility (Ks), intermolecular free length (Lf), acoustic impedance (Z), surface tension (), molar volume (Vm) and Wada's constant (W). From the data, the deviations in adiabatic compressibility (Ks), ultrasonic velocity (U), intermolecular free length (Lf) and acoustic impedance (Z) were calculated. The results are discussed in terms of molecular interaction among components of the ternary mixture. The theoretical values of ultrasonic velocity have been calculated using various empirical relations and are compared with the corresponding experimental data by calculating percentage deviation.

Toxicoproteomics of the mixture of Di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) in male sprague-dawley rats

Toxicoproteomics of the mixture of Di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) in male sprague-dawley rats

Regeneration of cobalt-contaminated activated carbon by supercritical carbon dioxide extraction

A mixture of Di-(2-ethylhexyl) phosphoric acid (D2EPHA) and n-hexane or methanol is used as the extractant solution for extracting cobalt from activated carbon using supercritical carbon dioxide extraction technology. In this work, a semi-continuous pilot unit of SFE is employed to conduct the extraction. In order to feed the viscous extractant by HPLC pump, n-hexane or methanol is added as a diluent to reduce the viscosity of the extractant. The amount of cobalt removed along the time course of the extraction is recorded and plotted as an extraction curve. A kinetic model is also established and fit to the extraction curve, and the obtained parameters of the model are used to explain the regeneration mechanism. The effects of temperature ranged from 40 to 80 °C and the effect of the concentration of diluents on the extraction are investigated and discussed based on the established model. It is also found that the removal of cobalt ions reaches a maximum; this varies with the operational conditions and is known as maximum removal efficiency. It is presumed that the maximum removal efficiency is affected by the adsorption kinetics of the extractant and the rate of ion exchange between the extractant and metal ions on the surface of the activated carbon. After increasing the extraction temperature from 60 to 80 °C it is observed that the maximum removal efficiency is greatly increased, presumably resulting from the diminishing competitive adsorption between the extractant and diluents. The established model can help to reveal the extraction mechanism and to promote maximum removal efficiency for regenerating activated carbon without secondary pollution.

Comparative determination of uranium in rock phosphates and columbite by ICP-OES, alpha & gamma spectrometry

During this work selective separation of uranium from rock phosphate and columbite mineral was done before its quantitative estimation by using Inductively Coupled Plasma Optical Emission Spectrometery (ICP-OES). Uranium from the rock phosphate and columubite was extracted by sodium peroxide fusion followed by leaching in 2 M HNO3. To avoid spectral interference in the estimation of uranium by ICP-OES, the selective separation of uranium from the leachate was carried out by using two different extractants, 30% Tributyl Phophates (TBP) in CCl4 and a equi-volume mixture of Di(2-ethylhexyl) phosphoric acid (D2EHPA) & TBP in petrofin. Uranium was stripped from the organic phase by using 1 M ammonium carbonate solution. Determination of uranium by ICP-OES was done after dissolving the residue left after evaporation of ammonium carbonate solution in 4% HNO3. The concentration of the uranium observed in the rock phosphates samples was 40–200 μg g−1 whereas in columbite samples the concentration range was 100–600 μg g−1. Uranium concentration evaluated by ICP-OES was complimented by gamma & alpha spectrometry. Concentration of uranium evaluated by gamma spectrometry in case of rock phosphate and coulmbite was in close agreement with the uranium content obtained by ICP-OES. Uranium determination by alpha spectrometry showed only minor deviation (1–2%) from the results obtained by ICP-OES in case of rock phosphates whereas in case of coulmbites results are off by 20–30%.

Structures of the dI2dIII1 Complex of Proton-Translocating Transhydrogenase with Bound, Inactive Analogues of NADH and NADPH Reveal Active Site Geometries,

Transhydrogenase couples the redox reaction between NADH and NADP+ to proton translocation across a membrane. The enzyme comprises three components; dI binds NAD(H), dIII binds NADP(H), and dII spans the membrane. The 1,4,5,6-tetrahydro analogue of NADH (designated H2NADH) bound to isolated dI from Rhodospirillum rubrum transhydrogenase with similar affinity to the physiological nucleotide. Binding of either NADH or H2NADH led to closure of the dI mobile loop. The 1,4,5,6-tetrahydro analogue of NADPH (H2NADPH) bound very tightly to isolated R. rubrum dIII, but the rate constant for dissociation was greater than that for NADPH. The replacement of NADP+ on dIII either with H2NADPH or with NADPH caused a similar set of chemical shift alterations, signifying an equivalent conformational change. Despite similar binding properties to the natural nucleotides, neither H2NADH nor H2NADPH could serve as a hydride donor in transhydrogenation reactions. Mixtures of dI and dIII form dI2dIII1 complexes. The nucleotide charge distribution of complexes loaded either with H2NADH and NADP+ or with NAD+ and H2NADPH should more closely mimic the ground states for forward and reverse hydride transfer, respectively, than previously studied dead-end species. Crystal structures of such complexes at 2.6 and 2.3 A resolution are described. A transition state for hydride transfer between dihydronicotinamide and nicotinamide derivatives determined in ab initio quantum mechanical calculations resembles the organization of nucleotides in the transhydrogenase active site in the crystal structure. Molecular dynamics simulations of the enzyme indicate that the (dihydro)nicotinamide rings remain close to a ground state for hydride transfer throughout a 1.4 ns trajectory.

Preparation and Characterization of HMW PA 6 via Anionic Polymerization of ∊-Caprolactam by Using a Mixture of Di- and Tri-functional Chain Initiators

Abstract In the present work, an attempt was made to synthesis polyamide 6 through anionic polymerization of e-Caprolactam by using a mixture of Diphenylmethan 4, 4-di and tri-isocyanate as a chain initiator and sodium caprolactamate as a catalyst. Polymerization was carried out in a laboratory internal mixer (Brabender). The rotor speed, reaction temperature and reaction time were among the processing variables studied. The prepared samples were characterized by Thermogravimetry Analysis (TGA), Differential Scanning Calorimeter (DSC) and FT-IR spectroscopy. The flow behavior and melt viscoelastic properties of the samples were studied by using a Rheometric Mechanical Spectrometer (RMS). The polymerization reaction was found to be very fast and was completed within 6 minutes. This was detected by following the mixing torque which reached to a steady state after passing through a maximum. The pronounced decrease in the torque was found to be determine by the thermomechanical degradation as a predominating mechanism. The polyamide 6 prepared in this work showed greater melt elasticity, much higher molecular weight and slightly narrower molecular weight distribution in comparison with the commercial grades of polyamide 6. The crystallinity of the samples was also higher than that of the commercial polyamide 6. These results were explained in terms of contribution of fraction of the molecules possessing single long chain branch formed as a result of three functional nature of the chain initiator. Increasing the rotor speed was found to have strong influence on lowering molecular weight as well as narrowing the molecular weight distribution through increasing the extent of thermomechanical degradation. Increasing the initial set temperature in the studied range had no appreciable effect on polymerization rate and degree of conversion. It was demonstrated that the results of melt viscoelastic measurements performed on the samples collected at different polymerization times can provide valuable information to follow the polymerization reaction.

Composition of the Organic Phase Species in the Synergistic Extraction of Sr2+ by Mixtures of Di(2‐Ethylhexyl) Alkylenediphosphonic Acids and Dicyclohexano‐18‐crown‐6†

The extraction of Sr2+, Ba2+ and Ra2+ from aqueous nitric acid solutions by P,P′‐di(2‐ethylhexyl) ethylene‐ (H2DEH[EDP]) and butylene‐ (H2DEH[BuDP]) diphosphonic acids in o‐xylene is synergized by the cis‐syn‐cis and cis‐anti‐cis stereoisomers of dicyclohexano‐18‐crown‐6 (DCH18C6). However, no information is available on the composition of the synergistic complexes. In this work a detailed investigation of the composition of the organic phase species formed in these systems has been performed using Sr2+ as a probe, with a variety of techniques such as infrared spectroscopy, vapor pressure osmometry, and distribution methods. The latter methods have been employed under conditions ranging from trace metal concentration to organic phase saturation. The results from these experiments indicate that for the H2DEH[BuDP] system, the synergistic complex contains one Sr2+ ion, one crown ether molecule, and two diphosphonic acid trimers. For the H2DEH[EDP] system, the predominant synergistic complex has the 1:1:1 metal ion:crown ether:diphosphonic acid hexamer stoichiometry. Some of the results, however, indicate that a complex containing two H2DEH[EDP] hexamers can also be formed. †Work performed under the auspices of the Office of Basic Energy Sciences, Division of Chemical Sciences, U.S. Department of Energy, under contract W‐31‐109‐ENG‐38. The submitted manuscript has been created by the University of Chicago as Operator of Argonne National Laboratory (“Argonne”) under Contract No. W‐31‐109‐ENG‐38 with the U.S. Department of Energy. The U.S. Government retains for itself, and others acting on its behalf, a paid‐up, nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government.

Crystal structure of a new (21)-clinopyribole synthesized at high temperature and pressure

A (21)-clinopyribole with the composition K 1.10 Na 2.32 Ca 1.52 Mg 5.85 Al 1.23 Si 12.04 O 34 (OH) 2 has been syn­thesized at 10 GPa and 1250 °C in a multi-anvil apparatus. The unit-cell parameters are a = 9.8390(9), b = 26.6471(6), c = 5.2665(5) Å, β = 106.25(5)°, and V = 1325.6(4) Å 3 . The structure (space group A2/m) consists of an alternating arrangement of single- and double-chain silicate slabs along the b axis, with a + + + + configuration. This phase possesses all the features predicted by Veblen and Burnham (1978b) for a mixed-chain silicate intermediate between pyroxenes and amphiboles. The single-chain portion of the structure corresponds to a clinopyroxene with the omphacite composition Di 55 Jd 45 , whereas the double chain portion is essentially a potassic richterite. The MS2 cation in the single-chain portion occupies a coordination environment that is similar to the M4 site in richterite, whereas the MD4 cation coordination in the double-chain portion is comparable to the M2 site in C2/c omphacite. The observed unit-cell volume is 1.5% smaller than the equivalent mixture of Di 55 Jd 45 + richterite, accounting, in part, for its high-pressure stability relative to its pyroxene and amphibole components.

Synergistic Solvent Extraction of Alkaline Earth Cations by Mixtures of Di-n-octylphosphoric Acid and Stereoisomers of Dicyclohexano-18-crown-6

The partitioning of Ca(II), Sr(II), and Ba(II) in solvent extraction systems comprising di-n-octylphosphoric acid (HDOP) and individual stereoisomers of dicyclohexano- 18-crown-6 (DCH18C6) in tolue...

Viscoelastic Characterization of an Order−Order Transition in a Mixture of Di- and Triblock Copolymers

The phase behavior and linear viscoelasticity of a mixture of a matched diblock and triblock copolymer of styrene and ethylene−butene-1 are reported. The mixture undergoes reversible thermotropic transitions from a cylindrically ordered state at low temperatures to a spherically ordered state at intermediate temperatures to a disordered state at high temperatures. The morphological assignments were based on TEM and SANS measurements, which also revealed a decrease in the domain size in the spherically ordered state as compared to the cylindrically ordered state. The kinetics of the order−order transition are extremely slow, with the sample exhibiting rheological characteristics similar to a disordered material immediately after heating from the cylindrical to the spherical state. The transition exhibits a long induction period wherein the sample continues to behave like a disordered material followed by a rapid increase in the storage modulus and a final plateau value. The kinetics and rheological charact...

Vapour Pressures at Eight Temperatures of Mixtures of Di‐n‐Propylether + Ethanol, or +1‐Butanol – Thermodynamic Description of Mixtures of Di‐n‐Propylether + Alkanol According to the ERAS Model

AbstractVapour pressures of di‐n‐propylether with ethanol and with 1‐butanol were measured at eight temperatures between 278.15 and 323.15 K by a static method. Reduction of the vapour pressures to obtain activity coefficients and excess molar Gibbs free energies was carried out by Barker's method. Mixtures containing ethanol show azeotropy with a minimum boiling temperature. GE, HE, and VE, at 298.15 K, of mixtures of di‐n‐propylether + methanol, + ethanol, + 1‐propanol, + 2‐propanol, and + 1‐butanol are compared with predictions of the ERAS model observing that the model reproduces acceptably the experimental behaviour.