Binary Extraction Research Articles

Zinc extraction from sulfate media with bis(2,4,4-trimethylpentyl)dithiophosphinic acid in the absence and in the presence of electron donor additives

The paper presents data on zinc extraction from sulfate solutions with bis(2,4,4-trimethylpentyl)dithiophosphinic acid (HR, trade mark CYANEX 301) diluted with nonane and kerosene in the absence and in the presence of electron-donor additives (L). Trialkyl amine (TAA), trialkyl phosphine oxide (TAPO), tributyl phosphate (TBP), and n-octanol were used as additives.Using the zinc distribution data and spectral methods, it was shown that, in the absence of additives, zinc extraction with CYANEX 301 proceeds by a cation exchange mechanism. The composition of the extracted compound in the organic phase was found to be ZnR2. In all cases, the introduction of additives into the organic phase results in a decrease in zinc extraction, which is probably due to a decrease in the extractant activity resulting from the interaction between HR and L. The degree of extraction decreases in the series HR without additives>HR+n-octanol>HR+TBP>HR+TAPO>HR+TAA.In the HR+TAA system, with increasing aqueous acidity, a change in the mechanism of zinc extraction from cation exchange to binary extraction takes place. In this case, the counter ion (bisulfate ion) is extracted together with the cation (zinc).The mixtures of HR with TAA could be of interest for zinc recovery from various industrial solutions, for example, in the processing of viscose rayon fibre solutions for the separation of zinc from calcium, for purification of zinc solutions from manganese, etc. Unlike the system containing only dithiophosphinic acid, both effective zinc extraction and its effective stripping with dilute solutions of sulfuric acid are possible for the HR+TAA system.

Radiotracer study of the effects of organophosphorus donors on the extraction of iron(III) with 2-hydroxy-N-phenylbenzamide in n-butanol

The behavior of Fe(III) in extraction from an aqueous chloride medium with 2-hydroxy-N-phenylbenzamide (HA) in n-butanol in the presence of several organophosphorus donors like trioctylphosphine oxide, triphenylphosphine oxide, and tributyl phosphate at pH 2.0 was studied using radiotracer technique. The overall equilibrium constants for each of the three ternary extraction systems and for the binary extraction system were calculated. The temperature dependences of the equilibrium constants were examined to evaluate the thermodynamic functions like enthalpy (ΔH0), entropy (ΔS0), and free energy (ΔG0). It was found that the extent of Fe(III) extraction into the organic phase both as the binary complex [FeA2Cl(H2O)] and as the ternary complex [FeA2Cl(S)] increases with temperature.

Skeleton-Based Feature Extraction Method for Two-Dimensional Potential Energy

A good feature extraction method can improve the performance of pattern recognition system or classification system. Using potential energy theory into binary image feature extraction and feature store is a new method for image processing. The skeleton can be better display the whole features of the object. In target recognition system, using potential energy of skeleton-point projection into the plane coordinate system. The method can be better to show a skeleton in the structural feature. In addition, it can better avoid the matrix storage redundancy. In all energy projection method, potential energy projection is better shown its superiority in the structure information, the time of consumption and the storage space. The skeleton potential energy can be used in target recognition and target classification field and so on.

Research on Evaluation of Corrosion Grade Based on Image Processing Technique

The corrosion images of LY12CZ aluminum alloy with different corrosion time were obtained from accelerated corrosion experiment. The changing law of pits corrosion ratio at different corrosion time and corresponding corrosion grade were attained through image processing technique based on binary characteristic extraction. A new thought of corrosion damage evolvement law for aluminum alloy was proposed based on Corrosion grade which was regarded as the evaluation standard of corrosion damage for aluminum alloy.

Extraction of platinum and palladium from hydrochloric solutions by trioctymethylammonium dinonylnaphthalenesulfonate

We investigated the phase distribution of chloride complex platinum and palladium acids in the presence of the binary extracting agent trioctylmethylammonium dinonylnaphthalenesulfonate. During the extraction of H2PtCl6 and H2PdCl4, the distribution coefficients were found to decrease as long as the pH value was growing, in full accordance with the known general trend of binary extraction. In contrast to the extraction variant using quaternary ammonium bases with inorganic counterions, a binary system, which was based on dinonylnaphthalenesulfonic acid, could be used for the further aqueous reextraction of platinum metals from the organic phase because of the higher thermodynamic stability of the binary reagent in the two-phase system.

Finger vein recognition using minutia-based alignment and local binary pattern-based feature extraction

With recent increases in security requirements, biometrics such as fingerprints, faces, and irises have been widely used in many recognition applications including door access control, personal aut...

Solvent extraction of some lanthanides from chloride and nitrate solutions by binary extractants

The solvent extraction of some rare earth metals (REM) from chloride and nitrate solutions by binary extractants, such as salts of trioctylmethylammonium with dialkylphosphinic, dialkylmonothiophosphinic, dialkyldithiophosphinic acids in toluene, as a function of the compositions of the aqueous and organic phases has been studied. The extraction isotherms of rare earth metals in trioctylmethylammonium bis(2,4,4-trimethylpentyl)phosphinate system were examined. The effect of binary extractant concentration in the organic phase and concentration of salt present in the aqueous phase (NaCl, NaNO 3) was also investigated. The ratio of C ex: C Ln(org) was found for REM chlorides close to 3, whereas that was found for REM nitrates close to 1 in the case of the loaded organic phase. Extraction efficiency of binary extractants towards lanthanum chloride as well as lanthanum nitrate decreases in the series: dialkylphosphinate > dialkylmonothiophosphinate >> dialkyldithiophosphinate of quaternary ammonium base (QAB). The separation factors of some metal pairs in the extraction of chlorides and nitrates of lanthanides were calculated using the experimental data obtained. Effective extraction systems involving binary extractants for separation of rare earth metals from chloride and nitrate solutions were found.

Solid-phase/supercritical-fluid extraction for liquid chromatography of phenolic compounds in freshwater microalgae and selected cyanobacterial species

In the present paper a new extraction technique based on the combination of solid-phase/supercritical-fluid extraction (SPE/SFE) with subsequent reversed-phase HPLC is described. The SPE/SFE extractor was originally constructed from SPE-cartridge incorporated into the SFE extraction cell. Selected groups of benzoic acid derivatives ( p-hydroxybenzoic, protocatechuic, gallic, vanillic and syringic acid), hydroxybenzaldehydes (4-hydroxybenzaldehyde and 3,4-dihydroxybenzaldehyde) and cinnamic acid derivatives ( o-coumaric, p-coumaric, caffeic, ferulic, sinapic and chlorogenic acid) were extracted. Cyclic addition of binary extraction solvent system based on methanol:water (1:1, v/v) and methanol/ammonia aqueous solution was used for extraction at 40 MPa and 80 °C. The p-hydroxybenzoic, protocatechuic, vanillic, syringic, caffeic and chlorogenic acid; 4-hydroxybenzaldehyde and 3,4-dihydroxybenzaldehyde were identified by HPLC-electrospray mass spectrometry in SPE/SFE extracts of acid hydrolyzates of microalga ( Spongiochloris spongiosa) and cyanobacterial strains ( Spirulina platensis, Anabaena doliolum, Nostoc sp., and Cylindrospermum sp.). For the identification and quantification of the compounds the quasi-molecular ions [M−H] − and specific fragments were analysed by quadrupole mass spectrometry analyzer. Our analysis showed that the microalgae and cyanobacteria usually contained phenolic acids or aldehydes at μg levels per gram of lyophilized sample. The proposed SPE/SFE extraction method would be useful for the analysis of different plant species containing trace amount of polar fraction of phenols.

Extraction of uranyl nitrate with a binary extractant based on di(2,4,4-trimethylpentyl)phosphinic acid

The extraction of uranyl nitrate with methyltrioctylammomium di(2,4,4-trimethylpentyl)phosphinate is compared to uranyl nitrate extraction with constituent cation-and anion-exchange extracting agents at various compositions of aqueous and organic phases. In UO2(NO3)2 extraction with quaternary ammonium nitrate and dialkylphosphinic acid solutions in toluene, the compounds (R4N)2UO2(NO3)4 and UO2A2, respectively, are formed in the organic phase. The binary extraction of uranyl nitrate is characterized by larger distribution ratios than extraction with the initial quaternary ammonium nitrate. Under saturation conditions, the capacity of the binary extractant is two times higher than the capacity of the anion-exchange extractant at the same concentration. Uranyl nitrate extraction with a binary extractant can yield, in the organic phase, complexes in which the uranyl ion either forms a salt with the anion of the organic acid or is incorporated into an extractable complex anion, depending on its thermodynamic stability in the heterogeneous system.

Effect of binary extractants and modifier–diluents systems on equilbria of propionic acid extraction

Propionic acid is an important carboxylic acid widely used in chemical industries. The recovery from aqueous waste streams and fermentation broth is of research interest. Extraction of carboxylic acids by reactive extraction using extractant-diluent, mixed extractants in diluents and extractants in mixed diluents etc. are emerging areas of study. With this aim reactive extraction of propionic acid was carried out to study: (i) effect of binary extractants (tri-n-octylamine(TOA):tri-n-butylphosphate (TBP), TOA:Aliquat 336 and TBP:Aliquat 336), (ii) effect of modifier (1-decanol) in different diluents (kerosene, n-octane, n-heptane, petroleum ether, butyl acetate, MIBK, 2-octanol, dodecanol, hexane) and (iii) effect of phase volume. Improved extractions using binary extractants and binary diluents were observed. Since liquid–liquid extraction is dependent on effect of modifier concentration, effect of phase volume, presence of single or binary extractants and binary diluents, the study will be useful in the design of reactive extraction process for propionic acid recovery.

Extraction of platinum-group metals from chloride solutions by salts of quaternary ammonium bases and binary extractants

Literature data are given on the extraction of platinum-group metals from hydrochloric acid solutions by salts of quaternary ammonium bases, as well as the authors’ data on the binary extraction of platinum metals from chloride solutions. The possibility is shown of using binary extractants based on quaternary ammonium bases (QABs) for efficient extraction and separation of platinum-group metals, as well as for simple reextraction of these metals from organic phases by water, contrary to the initial anion-exchange systems with QAB chlorides.

Extraction of mineral acids with methyltrioctylammonium dinonylnaphthalenesulfonate

The interphase distribution of hydrogen halides (HF, HCl, HBr, and HI) and oxygen-containing acids (H2SO4 and HClO4) in a system with the binary extracting agent methyltrioctylammonium dinonylnaphthalenesulfonate was studied. It was found in the extraction of mineral acids depending on the aqueous acidity, that the distribution ratios of mineral anions B m− decreased with pH in accordance of the laws of binary extraction. The extraction isotherms of mineral acids were obtained, and the apparent constants of extraction were calculated.

The thermodynamic functions of viscous flow activation and structural features of triethylene glycol-aprotic polar solvent binary extractants

The kinematic viscosity of triethylene glycol containing small admixtures of polar aprotic solvents (dimethylsulfoxide, N-methylpyrrolidone, and tetramethylenesulfone) was measured. The thermodynamic functions of viscous flow activation and the mean degree of association in the binary systems specified at 20–60°C were calculated and analyzed. The degree of solution structuring was found to be determined by the energy component of viscous flow activation per structural unit of the associates formed.

Synergistic extraction of rare earths(III) from chloride medium with mixtures of 1‐phenyl‐3‐methyl‐4‐benzoyl‐pyrazalone‐5 and di‐(2‐ethylhexyl)‐2‐ethylhexylphosphonate

AbstractThe synergistic effect of 1‐phenyl‐3‐methyl‐4‐benzoyl‐pyrazalone‐5 (HPMBP, HA) and di‐(2‐ethylhexyl)‐2‐ethylhexylphosphonate (DEHEHP, B) in the extraction of rare earths (RE) from chloride solutions has been investigated. Under the experimental conditions used, there was no detectable extraction when DEHEHP was used as a single extractant while the amount of RE(III) extracted by HPMBP alone was also low. But mixtures of the two extractants at a certain ratio had very high extractability for all the RE(III). For example, the synergistic enhancement coefficient was calculated to be 9.35 for Y3+, and taking Yb3+ and Y3+ as examples, RE3+ is extracted as RE(OH)A2.B. The stoichiometry, extraction constants and thermodynamic functions such as Gibbs free energy change ΔG (−17.06 kJ mol−1), enthalpy change ΔH (−35.08 kJ mol−1) and entropy change ΔS (−60.47 J K−1 mol−1) for Y3+ at 298 K were determined. The separation factors (SF) for adjacent pairs of rare earths were calculated. Studies show that the binary extraction system not only enhances the extraction efficiency of RE(III) but also improves the selectivity, especially between La(III) and the other rare earth elements. Copyright © 2006 Society of Chemical Industry

Identification of eddies from sea surface temperature maps with neural networks

This paper describes a new algorithm for automatic detection of Mediterranean water eddies from sea surface temperature (SST) maps of the Atlantic Ocean. The proposed approach looks at satellite images as textural patterns of water temperatures. Given a point of the map, information on the surrounding temperature gradient field is extracted through a binary mask and organized as a numerical vector of gradient angles. An artificial neural network (ANN) is trained to recognize those textural patterns of gradient angles that characterize eddy structures. Tested over a range of different binary extraction masks, the proposed identification system achieves accurate and robust learning results. Results are also characterized by very low rates of detection of false positives. The latter is particularly important because eddies occupy only a small portion of the ocean map area. Experimental comparison is carried out using Laws' method for texture analysis. The results show that the proposed gradient‐based algorithm allows similar performances with a reduced design effort. The complexity of the proposed approach also compares favourably to other methods for identification of mesoscalar phenomena published in the literature. Given the satisfactory accuracy of the results obtained, the gradient‐based approach may be preferable to current techniques as it is simpler and more easily reconfigurable.

High-resolution magnetic resonance imaging sinc-interpolation-based subvoxel registration and semi-automated quantitative lateral ventricular morphology employing threshold computation and binary image creation in the study of fatty acid interventions in schizophrenia, depression, chronic fatigue syndrome and Huntington's disease

SummarySerial high-resolution structural magnetic resonance imaging scans of the brain can now be precisely aligned, with six degrees of freedom (three mutually orthogonal translational and three rotational degrees of freedom around three mutually orthogonal axes), using a rigid-body subvoxel registration technique. This is driven by the in-plane point spread function for images acquired in the Fourier domain with data obtained over a bounded region of k-space, namely the sinc interpolation function, where sinc z = (sin z)/z, with z being any complex number (including zero). Computational subtraction of the three-dimensional Cartesian spatial representation matrices of serially acquired scan data allows for the determination of structural cerebral changes with great precision, since voxel signals from unchanged structures are almost completely cancelled. Thus changes readily show up against a background of noise. Furthermore, lateral ventricular changes can now be accurately quantified using a semi-automated method involving contour production, threshold computation, binary image creation and ventricular extraction. These techniques have been applied to the investigation of the effects on cerebral structure of intervention with fatty acids, particularly the long-chain polyunsaturated n-3 fatty acid eicosapentaenoic acid (EPA), in disorders such as schizophrenia, treatment-resistant depression, chronic fatigue syndrome (myalgic encephalomyelitis or ME), and Huntington's disease.

Structural study of trivalent lanthanide and actinide complexes formed upon solvent extraction

The coordination of the trivalent 4f ions, Ln = Nd3+, Eu3+ and Yb3+, as well as the trivalent 5f ion, Am3+, with diamide and dialkylphosphoric acid extractants, individually and in combination, was studied by use of X-ray absorption spectroscopy. These studies provide metrical information about the interatomic interactions between the f-ions (M3+) and the ligands, dihexylphosphoric acid (HDHP) and N,N'-dimethyl-N,N'-dioctylhexylethoxymalonamide (DMDOHEMA), that is of practical relevance to the control of metal-ligand binding in liquid-liquid extraction systems for the separation of trivalent actinide ions, An3+, from trivalent lanthanide ions, Ln3+. Through systematic variations of extraction conditions and extractant combinations, we have found that the HDHP complexes with M3+ involve MO6 coordination and distant M...P interactions, whereas the DMDOHEMA complexes with M3+ involve MO8 coordination. The combination of the EXAFS results with ancillary extraction data and IR results facilitates descriptions of the stoichiometries and structures of the molecular species formed in solution upon liquid-liquid extraction and leads to a new understanding of the binary extraction systems in terms of the strength and selectivity of An3+- vs. Ln3+-ligand interactions. This fundamental structure information affords insight into solvent extraction processes that are of contemporary and practical importance in heavy element chemistry and to environmentally related issues arising from the separation and disposal of radioactive materials, particularly actinides and selected fission products, in the field of nuclear waste reprocessing research.

Extraction Separation of Cd(II) and Zn(II) with Cyanex301 and Aqueous Nitrogen‐Donor Ligand TPEN

The extraction separation of Cd(II) and Zn(II) with an organodithiophosphorus extractant, bis(2,4,4‐trimethylpentyl)dithiophosphinic acid (Cyanex301), and a hexadentate ligand containing six nitrogen donors, N,N,N′,N′‐tetrakis(2‐pyridylmethyl)ethylenediamine (TPEN), was studied. When TPEN in amounts equimolar with divalent metal was added in the aqueous phase, most of TPEN molecules (>99%) were complexed with these divalent metals in the pH range above 2. Then, the extraction of Cd with Cyanex301 was little affected by the addition of TPEN, however, that of Zn was depressed remarkably and the extraction constant of Zn was reduced to less than 10−4 times that without TPEN. TPEN acts as a strong masking agent only for Zinc. The binary extraction tests of Cd and Zn were carried out under the conditions that the initial concentration of Cyanex301 was 0.0025 mol/L and TPEN in amounts equimolar with divalent metals was added in the aqueous phase. The separation factor of Cd was evaluated as 1000 at pH 4. TPEN is an excellent ligand that promotes the separation of Cd by adding slightly to the aqueous phase.

Geothermal Power Generation Worldwide: Global Perspective, Technology, Field Experience, and Research and Development

This article discusses the state of art in harnessing geothermal power for medium- and large-scale generation of electricity (and for space heating) worldwide. It reviews technology, field experience, research, and development, together with current, probable, possible and potential developments in the USA, developed, and developing countries in near future and long term.First, world consumption of geothermal energy is discussed. Here, worldwide installed capacities for geothermal electricity, the countries with the highest share of electricity generated from geothermal power, capacity factors, and direct use of geothermal energy is reviewed. Then, cost of renewable energy, i.e., current installation cost for electricity generation and heat generation, for biomass, solar photovoltaic, solar thermal, hydro, geothermal, wind, and tidal power is reviewed. Geothermal power in the United States is examined. Highlighted is heat flow, tectonic controls, types of geothermal systems, United States geothermal potential, geothermal energy in the United States, operating conditions for electricity generation, and environmental constraints.The central part of the article discusses field experience with innovative geothermal plants considering geothermal power plant analysis and design (optimization in design of geothermal power plants, optimization of prime movers, heat cycle considerations, resource considerations, and environmental considerations). A review of experimental plants (proposed systems and tested systems), and innovative power plants in commercial operation (low, moderate, and high enthalpy resources) is then discussed.The article goes on to examine R&D programs that are underway to significantly enhance the use of geothermal power. Highlighted is typical research and development projects such as enhanced heat transfer in air-cooled condensers, materials research, instruments for real time monitoring of geothermal processes, plant optimization, removal of non-condensable gases from binary power plants, silica and metals extraction, and small-scale power plant field verification projects. Geothermal drilling R&D is also reviewed.

Implementation of 3D moving target‐tracking system based on MSE and BPEJTC algorithms

In this paper, a new stereo 3D moving‐target tracking system using the MSE (mean square error) and BPEJTC (binary phase extraction joint transform correlator) algorithms is proposed. A moving target is extracted from the sequential input stereo image by applying a region‐based MSE algorithm following which, the location coordinates of a moving target in each frame are obtained through correlation between the extracted target image and the input stereo image by using the BPEJTC algorithm. Through several experiments performed with 20 frames of the stereo image pair with 640_480 pixels, we confirmed that the proposed system is capable of tracking a moving target at a relatively low error ratio of 1.29 % on average at real time.