Extraction Behaviour Of Copper Research Articles

An Investigation into the Extraction Behavior of Copper from Sulfate Leach Liquor Using Acorga M5640 Extractant: Mechanism, Equilibrium, and Thermodynamics

The extraction of copper from sulfate leaching liquor was investigated using Acorga M5640 commercial extractant in kerosene diluent. The effects of important factors such as the extractant concentration, contact time, liquor pH, and temperature were examined on the separation factor Cu/Fe and the extraction efficiency of copper. The results indicated that nearly 92.32% copper was extracted from the leach liquor at 10% (v/v) Acorga M5640 concentration, 1:1 aqueous/organic phase ratio, 20 min contact time, pH 2.5, and 25 °C temperature. Also, the further increase in the values determined had no positive impact on the extraction of copper. Under these conditions, the separation factor Cu/Fe was obtained about 29.64. The extraction mechanism was studied applying the plot of log(D) – 2 pH against log [extractant] and it proved the association of two moles of Acorga M5640 for the extraction of one mole of copper. McCabe–Thiele diagram was constructed and a single-step extraction process was found to obtain the maximum extraction. Additionally, thermodynamic data were investigated and the extraction process was endothermic and non-spontaneous at 298 K (ΔH = 27.05 and ΔG = 15.52 kJ mol−1). Moreover, the loaded organic phase was stripped and 80.94% copper was recovered after 20 min using 10% sulfuric acid concentration.

Extraction Removal of Copper from Yunnan Red Soil Using EDTA and Citric Acid

Extraction behaviour of copper from Yunnan red soil by EDTA and citric acid were investigated. The influencing factors of EDTA and citric acid extraction were obtained. The EDTA and citric acid composite extraction for copper was also tested. The result showed that the extraction of copper for the system of low concentration citric acid (0.003 mol/L EDTA+0.05 mol/L) can reach to 64.8%, which is very close to that for thesystem of high concentration citric acid (0.003 mol/L EDTA+0.1 mol/L citric acid) (64.9%), and is high than that for 0.01 mol/L EDTA (61.1% )and 0.1 mol/L citric acid (61.2%).

Extraction behavior of copper(II) ion with a hydrophobic amino-functionalized ionic liquid

We have prepared the hydrophobic amino-functionalized ionic liquid (IL) 1-(2-aminoethyl)-3-butylimidazolium hexafluorophosphate and investigated its extraction behavior for copper(II) ion as a model cation. The IL, due to the presence of an amino group, is capable of complexing Cu(II) in a ratio of 6:1. The parameters affecting the extraction efficiency were optimized. The IL-based liquid–liquid microextraction was successfully applied to the analysis of Cu(II) in an environmental water standard reference material. The results are promising in terms of liquid–liquid microextraction, separation, and preconcentration of Cu(II).

Study on the Cloud Point Extraction of Copper(II) from an Aqueous Sulfate Medium with N,N′-Bis(salicylideneaminoethyl)amine Polydentate Schiff Base into a Nonionic Surfactant Phase

A novel polydentate Schiff base extractant, N,N′-bis(salicylideneaminoethyl)amine (H2L), was successfully used in a cloud point extraction of copper(II) from aqueous sulfate solutions. The extraction process is based on the formation of a hydrophobic complex of copper(II)−H2L, which is subsequently extracted into the nonionic surfactant p-octylpolyethyleneglycolphenylether (Triton X-100) rich phase at a temperature above the cloud point temperature (CPT). The phase diagrams of the binary system, water−surfactant (Triton X-100), and the ternary systems, water−surfactant−salt (Na2SO4), were determined. The effects of the main experimental parameters such as pH, extractant concentration, and nonionic surfactant concentration on the extraction behavior of copper(II) with N,N′-bis(salicylideneaminoethyl)amine were studied. The percentage extraction was found to be significantly dependent on the aqueous solution pH. The extraction of copper(II) was observed in the pH range of (3 to 11). The stoichiometry of the extracted species of copper(II) was ascertained by the Yoe−Jones mole ratio method to have a composition of 1:1 (Cu:H2L). The optimum conditions of the extraction of copper(II) have been established as the following: (1) 2·10−3 mol·L−1 extractant; (2) 5 % (by weight) surfactant; (3) pH of 9; (4) 0.49 mol·L−1 Na2SO4; and (5) temperature of 65 °C.

Extraction Behavior of Copper(II) Cation Using Sulfonamide-type Polyanionic Chelators Having Ethylene Bridges

To research possible use of sulfonamide-type polyanionic chelators having ethylene bridges as extractants, extraction (cation-exchange) behavior of Cu2+ with several chelators was investigated. Tripod sulfonamide-type chelator, tris [2- (p-toluenesulfonamido) ethyl] amine, showed higher extractability than its monosulfonamide analog, 2- (p-toluenesulfonamido) ethylamine. Although the former can be generally considered as trianionic tetradentate chelator, on extraction of Cu2+, it acted as dianionic tridentate ligand and formed neutral 1: 1 complex having one coordinating H2O. The formed complex seems to be stabilized by chelate effect of the ligand and shielding effect of the coordinating sulfonamido group.

Liquid–liquid extraction of Cu(II), Co(II) and Ni(II) with salicylidèneaniline from sulphate media

For a fundamental study on the development of novel extraction divalent metal, the extraction behaviour of copper(II), cobalt(II) and nickel(II) is studied with salicylidèneaniline (SAN). The phenol group in the Schiff base moiety leads to a large increase in the percentage of transition metal ions. SAN has both good reactivity towards metal ions and solubility in organic solvents. The solvent extraction of copper(II), cobalt(II) and nickel(II) with salicylidèneaniline from sulphate media is studied with the following parameters: pH, concentration of the extractant and the nature of diluent. The stoichiometry coefficients of the extracted species are determined by the slope analysis method. The extraction reaction proceeds by cation exchange mechanism and the extracted species are: CuL2HL, CoL2HL and NiL2. The extaction constants are evaluated for the different diluents. Under suitable conditions of pH, the solvent extraction of cobalt(II) and nickel(II) in different diluents leads to third phase formation. This tendency is confirmed from numerical extraction constants for both metal cations (log K ex = −15.10 ± 0.03 for nickel(II) in CHCl3) and (log K ex = −12.56 ± 0.04 for cobalt(II) in CHCl3). The extraction efficiency is found to follow the order Cu(II) > Co(II) > Ni(II).

COPPER(II) COMPLEX WITH THE TETRADENTATE LIGAND 1,5-BIS (4-DITHIOCARBOXYLATE-1-DODECYL-5-HYDROXY-3-METHYLPYRAZOLYL)PENTANE. LIQUID-LIQUID EXTRACTION STUDY

The synthesis of the complex and the solvent extraction behaviour of copper(II) from acid solution (pH 0-5) was studied with the new reagent 1,5-bis(4-dithiocarboxylate-1-dodecyl-5-hydroxy-3-methylpyrazolyl)pentane (H2DTC) as extractant. The reagent acts as tetradentate ligand and the extracted specie was found to be CuDTC

Study of the copper distribution in contaminated soils of hop fields by single and sequential extraction procedures

Hop growing in Bavaria requires the use of copper containing fungicides against mildew, which results in an accumulation of copper in the upper soils to concentrations of up to approximately 450 mg kg −1. The naturally occurring concentration of copper is approximately 10–15 times lower. Several single and sequential extractions were performed in parallel to the determination of total copper content after aqua regia digestion. By these means copper mobility and retention, its availability to plants as well as its distribution in soils was assessed. Three agricultural soils and two soils from fallow land have been analysed to elucidate whether the copper distribution changes in relation to agricultural activities and to predict environmental risks due to the high copper concentrations. This work also focuses on the difficulties arising from different results when using single and sequential extraction procedures. EDTA, acetic acid, deionised water, ammonium nitrate and calcium chloride were used as single extractants for the functionally defined speciation. EDTA and acetic acid can be regarded as extractants for the plant-available species, while deionised water, NH 4NO 3 and CaCl 2 only release electrostatically weakly bound metals to estimate the mobile species. The extraction behaviour of copper in these procedures is discussed with respect to the quantities extracted from the contaminated and non-contaminated soils. The studies indicate that no vertical copper translocation is observed in the ground, but the main amounts are highly available to plants. Sequential extraction procedures were used for operationally defined speciation, quantifying copper in specific soil phases. The ‘five-step extraction scheme’ first applied, suggested by the Standard Measurement and Testing Programme of the European Community, overestimated the amounts of copper bound to the residual phase. This was mainly due to the non-specific nature of the reagents for the organic/sulfidic and crystalline iron oxide fraction. A second reason could be the fact that this scheme was developed for sediment and not for soil analysis. Therefore, the sequential extraction has been applied using an adapted method of Zeien and Bruemmer, using different extractants for the two phases. The copper distribution was different, showing that approximately 40–50% of the total copper was bound to the organic fraction and approximately 15–30% could be extracted with the iron oxides. The amounts in the residual fraction were much lower. After comparing the results of the different extraction procedures the environmental behaviour of copper and its risks for plants, micro-organisms and groundwater is discussed in brief.

Extraction behaviour of copper(II) and silver(I) with a thiacrown ether carboxylic acid, 2-(3,6,10,13-tetrathiacyclotetradec-1-oxy)hexanoic acid

The extraction behaviour of copper(II) and silver(I) with 2-(3,6,10,13-tetrathiacyclotetradec-1-oxy)hexanoic acid (TTCTOHA) was investigated at 25±0.1°C and ionic strength of 0.1. The value of the logarithmic distribution coefficient, log K DR of TTCTOHA between octan-1-ol and aqueous phases was determined to be 4.13. Copper(II) was extracted with TTCTOHA into octan-1-ol as CuL 2, where L represents the anionic species of TTCTOHA. The logarithmic extraction constant, log K ex(10), was determined at −7.42. Silver(I) was extracted with TTCTOHA into octan-1-ol as AgL and Ag 2L 2. The logarithmic distribution constant, log K DC, of AgL was estimated to be 0.49. On the other hand, silver(I) was extracted into 1,2-dichloroethane as AgL and the logarithmic extraction constant, log K ex(10), was determined to be −2.24.

No Evidence of the Monomer in the Extraction of Copper(II) with Carboxylic Acids Having Bulky Substituent at .ALPHA.-Position.

The extraction behavior of copper(II) with three carboxylic acids having a bulky substituent at the α-position was investigated in order to clarify the steric effect on the dimerization of copper(II) carboxylate extracted in benzene. Pivalate and 2-ethylbutyrate were found to be extracted only as a dimeric species Cu2L4(HL)2through the slope analyses, taking into account the formation constant of (1:1) copper carboxylate complex in the aqueous phase. A new computing method based on fixing the species to the composition, Cu2L4(HL)2, was proposed to estimate both the dimerization constant of carboxylic acid (K2, HL) and the extraction constant of the dimeric copper species (Kex(22)) for the case of carboxylic acid of higher carbon number in nonpolar solvents, and the extracted diphenylacetate was also found to be only a dimer as is usual. Consequently, under our experimental conditions, there was no evidence for the coextraction of monomeric copper(II) species caused by the steric hindrance as reported in other papers. Moreover, a linear relationship between log Kex(22) and log Ka was maintained by adding the three bulky substituent carboxylic acids.

Studies on the extraction of Copper(II) with 4-alkyldithiocarboxylate derivatives of 1-phenyl-3,5-dioxopyrazolidine

The extraction behaviour of copper(II) from acid solutions (pH 0–6) was studied with the new reagent 4-alkyldithiocarboxylate-3,5-dihydroxy-l-phenylpyrazol (HL; alkyl = n-butyl, n-dodecyl). The species extracted was found to be ML 2. The reagent was used to separate copper(II) from iron(III) in an acidic lixiviation solution of a mineral sample composed of enarguite (Cu 3AsS 4) and pyrite (FeS 2). Additionally, the extraction efficiency of this new reagent was compared with the commercially available LIX 984 N extradant of copper (II).

Liquid-liquid extraction of copper(II) with cyclic tetrathioethers

Liquid-liquid extraction of the divalent metal ions manganese(II), cobalt(II), nickel(II), copper(II), zinc(II) and cadmium(II) with 1,4,8,11-tetrathiacyclotetradecane was examined using the tetraphenylborate ion (TPB −) for the formation of the ion pairs. Copper(II) was quantitatively extracted into 1,2-dichloroethane, whereas the other metals were hardly extracted. The extraction behaviour of copper(II) with 12–16-membered cyclic tetrathioethers ([ n]aneS 4, where n represents the total number of carbon and sulphur atoms int he cyclic ligand ring) was examined. Chloroform and 1,2-dichloroethane were used as extraction solvents. The order of the extractability of copper(II) was as follows: [15]aneS 4 > [16]aneS 4 > [14]aneS 4 > [13]aneS 4 > [12]aneS 4 > at 2.5 × 10 −4 M of ligands, [16] aneS 4 > [15]aneS 4 > [14]aneS 4 > [13]aneS 4 > [12]aneS 4 at 2.5 × 10 −5 M of ligands. The extracted species were examined at ligand concentrations higher than 2.5 × 10 −4 M. Copper(II) was extracted with [13]aneS 4 and [16]aneS 4 as [CuL 2] 2+ (TPB −) 2 and [CuL 4] 2+ (TPB −) 2 depending upon the relative concentration of the ligand to copper(II). Where L represents cyclic tetrathioethers. The extracted species with [14]aneS 4 and [15]aneS 4 were [CuL 2] 2+(TPB −) 2 and [CuL 4] 2+(TPB −) 2, respectively. In case of [12]aneS 4, the following three species were observed depending upon concentrations of the ligand and TPB −: [CuL 2(OH)] +TPB −, [CuL 2] 2+(TPB −) 2 and [CuL 4] 2+ (TPB −) 2.

Diethyldithiocarbamate (DDTC) extraction of copper(II) and iron(III) associated with humic substances in water

The extraction behaviour of copper(II) and iron(III) was studied in the presence of humic substances (humic and fulvic acids) by using DDTC and chloroform. Copper-humic complexes were nearly completely extracted over the pH range 3–9, indicating that DDTC reacted with copper more strongly than humic substances. Iron-humic substances, mainly existing as hydrated iron(III) oxide covered with humic substances, were not extracted quantitatively (recovery <70%), though hydrated iron(III) oxide itself was extracted with greater than 93% yields at pH 5–9. For complete extraction of the humic species, ammonium pyrrolidinedithiocarbamate (APDC) was useful, because it allowed extraction from slightly acidic solutions where the binding of iron-humic substances became weak.

The Syntheses of Ortho-, Meta-, and Paracyclophane-Type Thiacrown Compounds and Their Characteristics as Extractive-Spectrophotometric Reagents for Class b Metals–Silver and Copper

Abstract Ortho-, meta-, and paracyclophane-type thiacrown compounds bearing 4-(4-nitrophenylazo)phenol as a chromogenic group were synthesized, and their characteristics as extractive-spectrophotometric reagents for the class b metals, consisting of soft Lewis acids such as silver and copper(I), were examined. Silver and copper(I) were well extracted into chloroform with all of three reagents, though especially with the metacyclophane-type reagent. The absorption maxima of silver and copper(I) complexes with the orthocyclophane-type reagents are at the longest wavelengths among the three reagents. The orthocyclophane-type reagent is adequate for the extraction and spectrophotometric measurement of copper(I), and the metacyclophane-type reagent is suitable for that of silver. The extraction behavior of copper(II) with these three reagents has been studied in order to know if the hydroxyl group participates in the formation of the metal–thiacrown complexes.

Liquid-Liquid Extraction of Metal Ions by Cyclic and Acyclic Tetrathio Ethers

Liquid-liquid extraction of metal ions with several cyclic and acyclic tetrathio ethers was examined using picrate as the anion of the ion pair. Three new acyclic compounds were synthesized. Class b metal such as Ag(I), Cu(I), Pd(II) and Hg(II) were extracted well, whereas class a and class ab metals were not extracted at all except for Cu(II) with each ligand, regardless of its being cyclic and acyclic tetrathio ethers. The extraction behavior of copper(I) was stoichiometrically examined. Copper(I) was extracted with five ligands(L) into 1, 2-dichloroethane as ion pair compounds, [Cu(I)L]+Pic-. The extraction constant Kex for copper(I) with each ligand was determined. Copper(I) is most effectively extracted with the tetrathio ether of the o-xylene derivative. It becomes clear that the configuration of ligands is reflected in the Kex value.

Liquid—liquid extraction of metal ions by the thiacrown compound 1,4,8,11-tetrathiacyclotetradecane

The possibilities of thiacrown compounds in liquid—liquid extraction were tested by using 1,4,8,11-tetrathiacyclotetradecane (TTCT). Class a metals were not extracted at all; of the class ab metals, only copper(II) was extracted. Class b metals were extracted but their extractabilities varied considerably. The relationship between the distribution ratio of the b metal and its softness is discussed. The extraction behavior of copper(I) with TTCT was studied in detail. The copper(I)—TTCT cation was completely extracted at pH > 4.0 as an ion-pair with perchlorate, picrate or tetraphenylborate. The extraction of copper(I) with TTCT and picrate into different solvents decreased in the order nitrobenzene >1,2-dichloroethane > chloroform > carbon tetrachloride. A study of the extraction equilibria for copper(I) with TTCT in the presence of the picrate (Pic −) showed that copper(I) and TTCT form a 1:1 cation complex [Cu(TTCT)] +, which reacts with picrate to form the 1:1 ion-pair [Cu(TTCT)] +Pic −. The extraction constants are log K ex = 7.3 ± 0.3 and 9.0 ± 0.2 for chloroform and 1,2-dichloroethane, respectively, as the organic solvent.

Effect of washing on the kinetic stability of the copper(II)/APCD/IBMK system in strongly acidic media

The extraction behaviour of copper(II) with ammonium 1-pyrrolidinecarbodithioate in isobutyl methyl ketone has been investigated at various acidities of the aqueous phase. The chelate is produced even under strongly acidic conditions (0.01–6 M), and if the organic phase is washed with water it remains stable for at least 1 hr. The extraction is quantitative over the entire range of acidity.