Extraction Equilibrium Constants Research Articles

Extraction spectrophotometry using a lithium-ion selective metallacrown: temperature effect on extraction reaction and application to determination of lithium in serum and seawater

A metallacrown-type ionophore, 2,3-pyridinediolate-bridged (3,5-dimethylanisole)ruthenium trinuclear complex, has a high extraction selectivity for Li+, but the extraction reaction is very slow. To solve this problem, the effect of temperature on the rapidity and equilibrium of the extraction of Li+ and Na+ as picrates from water to toluene with the metallacrown was investigated in this study. While the extraction of Li+ requires 6 h of shaking for equilibration at 25 °C, the distribution ratio becomes nearly constant after 4 h and 2 h of shaking at 37 °C and 50 °C, respectively. The extraction equilibrium constants (Kex) and associated thermodynamic parameters determined for Li+ and Na+ indicate that the extraction reactions are exothermic and enthalpy-driven: ΔH° = − 53 kJ/mol, ΔS° = − 0.03 kJ/(mol K) for Li+; ΔH° = − 28 kJ/mol, ΔS° = − 0.03 kJ/(mol K) for Na+. Although the extraction ability for Li+ and selectivity for Li+/Na+ decrease with increasing temperature, the values of Kex and Kex(Li+)/Kex(Na+) are 1.0 × 107 and 1.3 × 104, respectively, even at 50 °C, indicating that both are sufficiently high. In the determination of Li+ by extraction spectrophotometry using this metallacrown, extraction at 50 °C for 2 h was employed to speed up the analysis. The method was applied to seawater and serum samples containing a large amount of coexisting ions such as Na+ and Mg2+, and trace amounts (10−6–10−5 mol/L order) of Li+ in microvolume samples (sub-mL order) could be successfully determined.Graphical abstract

The Extraction Mechanism of Zirconium and Hafnium in the MIBK-HSCN System

The extraction of zirconium (Zr) and hafnium (Hf) in methyl isobutyl ketone (MIBK)—thiocyanic acid (HSCN) system has been widely used in the production of nuclear-grade zirconium and hafnium in industry, while the extraction mechanism was not adequately studied. In this study, the extraction and stripping equilibrium of Zr and Hf in the MIBK-HSCN system was studied. The results showed that elevated HCl concentration can increase the distribution ratio of SCN− and decrease that of Zr/Hf in organic phase. In the stripping process, HCl concentration and the Organic/Aqueous (O/A) phase ratio played important roles. The mechanism of the extraction reaction was discussed by considering the stoichiometric relationship of possible reaction equations and corresponding equilibrium constants. The results indicated that SCN− could be extracted into MIBK as HSCN·MIBK. Meanwhile, SCN− could also be extracted into MIBK by complexing with metal (Zr or Hf). The molar ratios of MIBK to the complexes of Zr and Hf have been found to be 5.34 and 5.03, respectively. With the increase in the initial concentration of HCl in the aqueous phase, the complexation molar ratios of SCN− to Zr and Hf increased first and then decreased, and so do the extraction equilibrium constants, which might be due to the extraction competition of HSCN and metal complexes.

Sustainable process development for the recovery of biobased levulinic acid through reactive extraction

AbstractBACKGROUNDLevulinic acid is one of the top ten bio‐derived platform chemicals essential for producing many products that are used daily. The recovery of biobased chemicals from industrial streams and fermentation broths is critical due to environmental issues. A few studies have used chemical solvents for the recovery of levulinic acid, but these solvents are toxic for microorganisms. Therefore, green and cheap solvents for the separation of levulinic acid are needed. This study used sunflower oil as a green solvent with trioctylamine and tri‐n‐butyl phosphate for the separation of levulinic acid. The experimental study was presented in the form of important parameters, viz., distribution constant, loading ratio, extraction equilibrium constant, diffusion coefficient, and extraction efficiency. Fourier transform infrared spectroscopy (FTIR) was employed to understand the acid and extractant interactions and 1:1 complex formation was confirmed in organic phase.RESULTSThe experimental results include the distribution coefficients (0.14–0.81 and 0.23–2.15), loading ratios (0.013–0.709 and 0.023–0.53), extraction efficiencies (12.43–44.68% and 19–68.30%), and extraction equilibrium constants (0.47–1.63) with trioctylamine and tri‐n‐butyl phosphate, respectively. Since a single‐stage does not provide sufficient extraction efficiency, multi‐stage extraction was performed. The multistage design shows that trioctylamine and tri‐n‐butyl phosphate must be used in three and five stages, respectively, to get 94.8% and 97% recovery of levulinic acid.CONCLUSIONThis study describes the recovery of levulinic acid from the aqueous phase using trioctylamine and tri‐n‐butyl phosphate with sunflower oil as a sustainable green solvent. The multistage design setup provided approximately 100% recovery of levulinic acid.

Mathematical model and reaction mechanism of molybdenum and tungsten extraction with TRPO from peroxide solution

To understand the behavior of molybdenum and tungsten extracted by tri-alkyl phosphine oxide (TRPO) from peroxide solution, the extraction mechanism was studied by slope method and Raman and FTIR spectroscopy. The empirical formulas of molybdenum and tungsten extraction distribution ratio (DMo and DW) as functions of equilibrium pH, TRPO concentration and temperature were obtained by establishing mathematical models. Furthermore, the reliability of the empirical formula was verified in the H+−W−Mo−H2O2 solution. The results indicate that the calculated values of DMo or DW were consistent with the experimental values. The apparent extraction equilibrium constants of molybdenum and tungsten were =8.51×103 (0.74≤pHe≤1.7), =99.89×103 (1.7<pHe≤4.62) and =2.65×103 (0.92<pHe<2.16) at 20 °C, respectively. The main extraction complex of molybdenum or tungsten was [H2(Mo or W)2O3(O2)4(H2O)2]·2TRPO. These empirical formulas can be used to analyze and estimate the extraction and separation of Mo and W from low molybdenum and tungsten concentration solutions.

Thermodynamic and kinetic parameters of iodine extraction from chloride aqueous solutions

Extraction is a versatile and relatively simple method for extracting rare and scattered elements, producing good results at minimal expenses in terms of reagents and equipment. Information about the thermal effects and kinetic dependencies of the extraction process is essential for predicting and counteracting fluctuations in external conditions. In this work, the thermodynamic and kinetic parameters of the iodine extraction process were studied using model solutions that contained sodium chloride with an ionic strength of 0–5 mol/l as a background mineralization. This composition closely corresponds to natural and man-made waters of oil and gas condensate fields. A mixture of tri-n-butyl phosphate and isooctane was used as the extractant. In order to evaluate thermodynamic parameters, extraction isotherms were constructed at temperatures of 278 and 288 K. For different background ionic strength values, equilibrium extraction parameters were determined, including the extraction degree, distribution coefficient and equilibrium constant, as well as changes in the enthalpy, entropy and Gibbs energy of the process. A study of the kinetic dependencies of iodine extraction from aqueous solutions under different ionic strength values at temperatures of 278, 288 and 293 K allowed the true and apparent orders of reaction to be established, along with the activation energy of the extraction process. Across the entire range of the studied ionic strength values, iodine extraction occurs spontaneously with high distribution coefficients and an extraction degree of over 86%. The kinetic parameters of the iodine extraction process (activation energy, temporal and concentration reaction order) indicate the diffusion nature of the rate-determining step, the presence of intermediate complexation stages and the absence of temperature effects on the reaction rate.

Cyclic Voltammetry as a Probe of Selective Ion Transport within Layered, Electrode-Supported Ion-Exchange Membrane Materials

Cyclic voltammetry was applied to investigate the permselective properties of electrode-supported ion-exchange polymer films intended for use in future molecular-scale spectroscopic studies of bipolar membranes. The ability of thin ionomer film assemblies to exclude mobile ions charged similarly to the polymer (co-ions) and accumulate ions charged opposite to the polymer (counterions) was scrutinized through use of the diffusible redox probe molecules [Ru(NH3)6]3+ and [IrCl6]2−. With the anion exchange membrane (AEM) phase supported on a carbon disk electrode, bipolar junctions formed by addition of a cation exchange membrane (CEM) overlayer demonstrated high selectivity toward redox ion extraction and exclusion. For junctions formed using a Fumion® AEM phase and a Nafion® overlayer, [IrCl6]2− ions exchanged into Fumion® prior to Nafion® overcoating remained entrapped and the Fumion® excluded [Ru(NH3)6]3+ ions for durability testing periods of more than 20 h under conditions of interest for eventual in situ spectral measurements. Experiments with the Sustainion® anion exchange ionomer uncovered evidence for [IrCl6]2− ion coordination to pendant imidazolium groups on the polymer. A cyclic voltammetric method for estimation of the effective diffusion coefficient and equilibrium extraction constant for redox active probe ions within inert, uniform density electrode-supported thin films was applied to examine charge transport mechanisms.

Extraction equilibrium of molybdenum(VI) and tungsten(VI) in aqueous solutions containing hydrogen peroxide by synergistic solvent extraction with TRPO and TBP

The separation of molybdenum from peroxotungstate solution with neutral phosphorus extractant such as trialkyl phosphine oxide (TRPO), tri-butyl phosphate (TBP) is often accompanied by extraction loss of tungsten, which greatly reduces the separation efficiency. To solve the above problems and optimize process, clarifying the reaction equilibrium of extraction is necessary. However, relevant research, especially the TRPO-TBP synergistic system, has not been reported. Here, based on the effect of extractant concentration and equilibrium pH on Mo and W extraction with three extraction systems (TRPO, TBP and TRPO-TBP), the Mo and W distribution equations in the two phases and the stoichiometry of chemical reactions were determined via slope analysis. The apparent extraction equilibrium constants and cumulative protonation constant of [Mo2O3(O2)4]2− were calculated by successive-approximation method. The order of the extraction equilibrium constants is as follows: logKMo-TRPO-H (5.8) > logKMo-TRPO-TBP-H (4.3) > logKMo-TRPO (3.8) > logKW-TRPO (3.7) > logKMo-TRPO-TBP (2.3). The synergistic mechanism of TBP for Mo and W extraction was revealed through Raman, FT-IR and 31P NMR spectroscopy, proposing a synergistic extraction compound TBP·[H2Mo2O3(O2)4·2H2O]·TRPO. The experimental results showed that keeping a higher equilibrium pH (2–2.5) can improve the separation efficiency of W and Mo, which verified the feasibility of optimization measure proposed based on equilibrium data. This study reveals the extraction mechanism of W and Mo in H+-H2O2/TRPO-TBP system, which can provide some reference for the optimization of separation process.

Extraction of phenol from water by primary amine primene JMT

In this work, liquid-liquid extraction of phenol from aqueous solutions using primary amine Primene JMT (Primene® JM-T) was investigated. The extraction capability of Primene® JM-T with different diluents, including 3-heptanone, sulfonated kerosene, methyl isobutyl ketone, n-octanol, toluene and petroleum ether was studied. The experimental results indicated that the distribution coefficient of phenol extracted using Primene® JM-T that was diluted in 3-heptanone could reach 101.74 under the pH of 9.2. Moreover, the extraction reaction was exothermic (enthalpy change for the extraction reaction (ΔrHm) was −21.03 kJ/mol). High temperature showed a negative effect on the extraction of phenol. The results also showed that adding mineral salt was conducive to the extraction process, and the extraction efficiency fell in the descending order of: (NH4)2SO4> NaCl > NH4Cl. Two empirical correlations were put forward to quantitatively describe the salting effect. Furthermore, the equilibrium constants of phenol extraction using Primene® JM-T were calculated to be 78.2 L/mol. The phenol was extracted using Primene® JM-T with the possible stoichiometric formula of: [RNH3+⋅PhOH]org, where R represents the alkyl group of the amine.

Comparative Extraction of Aluminum Group Metals Using Acetic Acid Derivatives with Three Different-Sized Frameworks for Coordination

We prepared acetic acid derivatives using three different frameworks, calix[4]arene, alkenyltrimethylol, and trihydroxytriphenylmethane, which differ in the number and size of their coordination sites. We further investigated the extraction properties for aluminum group metal ions. All three extraction reagents exhibited increased extraction compared with the corresponding monomeric compounds, owing to structural effects. The extraction reaction and extraction equilibrium constants were determined using a slope analysis. Their extraction abilities, separation efficiencies, and potential coordination modes are discussed using the extraction equilibrium constants, half-pH values, and spectroscopic data. The calix[4]arene and trihydroxytriphenylmethane derivatives demonstrated allosteric co-extraction of indium ions (In3+) with an unexpected stoichiometry of 1:2.

Optimization of vanadium(V) extraction by 2-ethyl-1-hexanol and the study of extraction reaction mechanism

The aims of the present work are to investigate the mechanism and thermodynamics of pentavalent vanadium (V(V)) extraction by 2-ethyl-1-hexanol and to optimize the extraction process. The stoichiometry of V(V) extraction reaction and the extraction equilibrium constants at different temperatures were determined using the slope analysis method applied to the experimental data. It was shown that the extracted V(V) was in the form of HVO3(ROH) in the organic phase. The standard enthalpy and the standard entropy of extraction reaction were calculated as 39.56 kJ/mol and 54.38 J/(mol.K), respectively. A statistical experimental design method, including Plackett-Burman design (PBD) followed by a central composite design (CCD), was employed to obtain the regression models for the prediction of extraction percentages and to optimize the recovery of V(V) from a synthetic leach solution containing Fe(III), U(VI), Si(IV), and Al(III). The accuracy of the predictive models was proven by the analysis of variance (ANOVA). The optimum condition for selective separation of V(V) was: initial pH of 1.9, extractant concentration of 70 %v/v, and T=59.3 °C. Under the optimum condition, the extraction percentages for V(V), Fe(III), U(VI), Si(IV), and Al(III) were 91.3%, 1.7%, 6.3%, 10.6%, 2.7%, respectively. Developed models were validated by solvent extraction experiments at optimum conditions.

Revaluating solvent extraction equilibria of trivalent rare earths with EHEHPA (PC-88A) using Alstad equation

The equilibria associated with the solvent extraction of trivalent rare earth elements (REEs) with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHEHPA) have been previously studied by many researchers because of the industrial importance of REEs. However, quantitative analysis has been limited to relatively low concentrations of EHEHPA because of the nonideal characteristics of the organic phase. In the present paper, we used an empirical equation to correct the nonideality of the organic phase and calculated extraction equilibrium constants for some trivalent REEs (La, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Y) that are particularly important in RE recycling from end-of-life products and in-plant scraps. Calculations based on use of EHEHPA in a nonpolar diluent and a nitrate medium were used to systematically investigate equilibria at a constant ionic strength of 1 mol/L, temperature of 298 K, EHEHPA dimeric concentrations that ranged from 0.04 to 0.33 mol/L, and a range of pHs. Apparent extraction equilibrium constants that reproduced the distribution ratios of the REEs with good accuracy were obtained. Further experiments at higher EHEHPA concentrations revealed that the empirical equation was effective up to an EHEHPA dimer concentration of 0.5 mol/L, which is significantly higher than the upper bound for the conventional dimer model. Separation factors defined as the ratios of the distribution ratios of two REEs were calculated from the extraction equilibrium constants for the possible pairs of REEs and compared critically with literature values. Differences in the separation factors depended on the measurement conditions and were most pronounced when the difference in atomic numbers of the REEs was large. The results are expected to facilitate designing processes for the separation and purification of REEs.

Understanding the Mechanism of Lithium Ion Extraction Using Tributyl Phosphate in Room Temperature Ionic Liquid

ABSTRACT This paper reports the liquid-liquid extraction behavior of lithium ions from aqueous solutions containing hydrochloric acid using a well-known neutral extractant tri-n-butyl phosphate (TBP) and commonly used imidazolium-based ionic liquids (IL). The effect of several experimental parameters on the lithium partitioning was examined, in particular the nature of counter anions, the concentration of TBP, the pH of the aqueous solutions, and the initial lithium ion concentration. The lithium extraction was also investigated with a conventional organic solvent 1-octanol to understand the role of the IL in the extraction process. Our results suggest that lithium partition into TBP/IL system proceeds via two mechanisms, namely by cationic exchange and ion pair transfer. The corresponding extraction equilibrium constants as well as stoichiometry of extracted complexes were determined. To overcome the loss of ionic liquid by cation exchange, we have shown that TBP mixed with an ionic liquid possessing low solubility in aqueous phases can extract lithium when a highly hydrophobic counter-ion such as () is present in the aqueous phase.

Extraction and stripping behaviors of 14 lanthanides from nitric acid medium by N,N’-dimethyl-N,N’-dioctyl diglycolamide

N,N’-dimethyl-N,N’-dioctyl diglycolamide (DMDODGA) in 40/60 (V/V)% 1-octanol/kerosene was used to extract 14 lanthanides from nitric acid solution. The effects of the aqueous acidity, the DMDODGA concentration, and the temperature on the distribution ratio of Ln(III) were investigated. The extraction equilibrium constants K and the thermodynamic parameters were determined by the slope analysis method combined with Pitzer model. The IR spectra of the extracted species and pure extractant were recorded and analyzed. Moreover, 0.001 mol/L nitric acid is the suitable stripping agent, and the stripping efficiency of all lanthanides can reach up 90% by three times of stripping.

Extraction of Cobalt and Lithium from Sulfate Solution Using Di(2-ethylhexyl)phosphoric Acid/Kerosene Mixed Extractant

The solvent extraction behavior of cobalt and lithium from mixed sulfate solution using di(2-ethylhexyl)phosphoric acid (D2EHPA)/kerosene as extractant system has been investigated. The effect of different process parameters such as pH of feed solution, extractant concentration, cobalt and lithium ion concentrations in the feed solution have been studied. Extraction equilibrium constants have been calculated and found to be log Kex Co = –2.01 and log Kex Li = –2.42. The highest separation factor of 292 was achieved using 1.59 M D2EHPA at pH 1.85 from mixed sulfate solution. 93.9% of cobalt and 11.4% lithium was co-extracted from 0.01 M cobalt and lithium sulfate solution. Extraction of cobalt-lithium by D2EHPA is affected by cation exchange mechanism, cobalt is extracted as [Co(HA2)2] and [CoA2] depending on the metal concentration in the feed solution while the lithium is extracted as [Li(A2H)]. Quantitative extraction of cobalt was achieved in two-stage counter-current batch extraction (with McCabe–Thiele plot) using 0.477 M D2EHPA at an O : A phase ratio of 1. The data obtained from loaded organic and raffinate indicate a composition which reveals nearly complete extraction of cobalt and rejection of lithium resulting significant separation of these elements from mixed sulfate solution.

A Preliminary Study of Extraction and Purification Processes of Astaxanthin from Haematococcus pluvialisas a Natural Antioxidant

Haematococcus pluvialisis is a species of microalgae which contains a prominent natural antioxidant called astaxanthin. However, the thickness of microalgae cell wall hinders the extraction process. This problem (cell wall destruction) can be overcome by implementing one of the efficient methods, microwave assisted extraction. The purpose of this study is to determine the extraction equilibrium constant and simple experiment data on purification process. The extraction was carried out using acetone as the solvent at 50°C under constant stirring speed which was then followed by refinement process. Thin layer chromatography was also performed to select the suitable eluent for purification that drew upon chromatographic column. Based on the experiment, the best eluent from thin layer chromatography was a mixture of acetone and petroleum ether 1:1 (v/v), with the retardation factor (Rf) value of 0.649 under atmospheric pressure. Likewise the highest astaxanthin purity was 6.451mg/L. Meanwhile, the equilibrium constant was investigated by employing the mathematical modeling.

Study on Extraction Kinetics of Tartaric Acid and Pectin from Tamarindus indica

The objective of this work was to investigate the reactive extraction of tartaric acid and pectin in model frameworks. Tamarind pulp comprises organic acids like citric acid, tartaric acid, malic acid along with pectin. Extraction of tartaric acid and pectin from tamarind pulp was performed utilizing ethanol and inorganic acid as a solvent respectively at 25°C and 50°C. The values of the extraction equilibrium constants were found to be 0.018, with R2 esteem extending from 0.95 to 0.98, at various stirring speeds. The obtained solid form of tartaric acid was detected by Thin Liquid Chromatography (TLC) and its concentration analyzed with UV spectrophotometer by measuring the absorbance value at 505nm. The extracts obtained from process are treated with HCl and were analyzed by TLC. The effect of temperature on the extraction rate is pitiful and the thermodynamic property such as Gibb's free energy for the extraction process was found to be −190 to-206 kJmol−1. The reduction in ΔG° values demonstrates the attainability of procedure as the temperature increments from 25°C to 50°C.

Synthesis and Characterization of Novel Ag(I)-15C5 Complexes

Crown ethers have been used for the various studies pertaining to extraction equilibrium constant, stability constant and for determination of some of the alkali and alkaline earth elements and other elements from p, d and f-block elements. Crown ethers have a significant coordination power towards silver ion. The present paper describes synthesis and characterization of novel Ag(I) complexes with 1, 4, 7, 10, 13,-pentaoxacyclooctadecane (15-crown-5 ether), having five donor ‘oxygen’ atoms. The organic salts used for complexation were salts of nitrophenols. Products were isolated from silver salts of all the three nitrophenols, 2-nitrophenol (ONPH), 2, 4-dinitrophenol (DNPH) and 2, 4, 6-trinitrophenol (TNPH), having general formula of [Ag. L](Pic-), where L = 15C5 and Pic-= Picrate anion. The bonding pattern and structure of complexes were suggested from elemental analysis, molar conductivity, UV-Vis, IR, and 1H-NMR spectral analysis.

Separation and Recovery of Scandium from Sulfate Media by Solvent Extraction and Polymer Inclusion Membranes with Amic Acid Extractants.

We report on the separation and recovery of scandium(III) from sulfate solutions using solvent extraction and a membrane transport system utilizing newly synthesized amic acid extractants. Scandium(III) was quantitatively extracted with 50 mmol dm–3N-[N,N-di(2-ethylhexyl)aminocarbonylmethyl]glycine (D2EHAG) or N-[N,N-di(2-ethylhexyl)aminocarbonylmethyl]phenylalanine (D2EHAF) in n-dodecane at pH 2 and easily stripped using a 0.5 mol dm–3 sulfuric acid solution. The extraction mechanisms of scandium(III) extraction with D2EHAG and D2EHAF were examined, and it was established that scandium(III) formed a 1:3 complex with both extractants (HR), that is, Sc(SO4)2–aq + 1.5(HR)2org ⇄ Sc(SO4)R(HR)2org + H+aq + SO42–aq. The equilibrium constants of extraction were evaluated to be 4.87 and 9.99 (mol dm–3)0.5 for D2EHAG and D2EHAF, respectively. D2EHAG and D2EHAF preferentially extracted scandium(III) with a high selectivity compared to common transition metal ions under high acidic conditions (0 < pH ≤ 3). In addition, scandium(III) was quantitatively transported from a feed solution into a 0.5 mol dm–3 sulfuric acid receiving solution through a polymer inclusion membrane (PIM) containing D2EHAF as a carrier. Scandium(III) was completely separated thermodynamically from nickel(II), aluminum(III), cobalt(II), manganese(II), chromium(III), calcium(II), and magnesium(II), and partially separated from iron(III) kinetically using a PIM containing D2EHAF as a carrier. The initial flux value for scandium(III) (J0,Sc = 1.9 × 10–7 mol m–2 s–1) was two times higher than that of iron(III) (J0,Fe = 9.3 × 10–8 mol m–2 s–1).

Extraction of scandium and other rare earth elements with a tricarboxylic acid derivative of tripodal pseudcalix[3]arene prepared from a new phenolic tripodal framework

We prepared a phenolic tripodal type extraction reagent to investigate the extraction of a series of rare earth metal ions. The extraction reaction and equilibrium extraction constants for rare earth ions with the tripodal extractant were evaluated using slope analysis and Job’s method. The tripodal reagent exhibited remarkably high extraction ability compared with a corresponding monopodal compound, and exhibited different extraction selectivities for rare earth metal ions than a calix[4]arene derivative because of the different size of the coordination site. The developed phenolic tripodal extraction reagent provides a new framework with a different size coordination site to those in calix[4]arene and alkyltrimethylol type tripodal compounds.

Recovery of Ga(III) from chloride solutions by solvent extraction with Cextrant 230

In the present work, an α-aminophosphonate extractant di(2-ethylhexyl) [N-(2-ethylhexyl)aminomethyl] phosphonate (Cextrant 230, L) was applied for the selective extraction and recovery of Ga(III) from the chloride solutions. The extraction of Ga(III) was compared with that of other metal ions such as Fe3+, Fe2+, Zn2+, Al3+, Mg2+ and Sn2+. The extracted complex of Ga(III) was deduced to be HGaCl4·L. The extraction equilibrium constant and thermodynamic parameters (ΔG, ΔH and ΔS) were calculated. The positive value of ΔH indicates that the extraction reaction of Ga(III) is an endothermic process. The loading capacity of 30% (v/v) Cextrant 230 for Ga(III) was determined to be 0.38 mol/L. The loaded gallium can be complete stripped by distilled water. A process was established for the selective recovery of Ga(III), by which the purity of the gallium product reached 94% with a yield of 89.5%