Polyaminoalkohole als bifunktionelle Extraktionsmittel für Kupfer(II)

Polyamino Alcohols as Bifunctional Extractants for Copper(II) Polyamino alcohols obtained by the addition of mono- or bifunctional epoxides to disecondary diamines are studied with regard to their applicability to copper(II) extraction. The simple diamino diols IV, V , and VI proved to be inefficient. But, depending on the anion, distribution ratios D up to 1000 were measured with the polyamino alcohol III (chloroform as a diluent) in weakly acidic solution. This is a result of the special structure of the copper(II) complex of III which is both a metal chelate and a substituted ammonium salt. The ammonium part, because of its high affinity to the chloroform phase, has the function of a phase-transfer reagent of the chelate part.     

Extraction and complexing of copper(II) with benzoic acid N,N-dihexylhydrazide

The solubility and acid-base properties of benzoic acid N,N-dihexylhydrazide (BDHH) were studied. The extraction of copper(II), cobalt(II), nickel(II), zinc(II), iron(III), platinum(II), platinum(IV), chromium(III), chromium(VI), palladium(II), and molybdenum(VI) with this reagent was studied. It was shown that BDHH most efficiently extracts copper(II) from ammonia solutions and chromium(VI) from sulfuric acid solutions. In the extraction of copper(II), complexes with the [Cu(II)]: [BDHH] = 1: 1 and 1: 2 stoichiometries were found to form. The structure of the 1: 2 complex was suggested proceeding from its IR spectra. A copper(II) extraction isotherm was plotted.     

Homo‐ and heteropolynuclear copper(II) complexes containing a new diimine–dioxime ligand and 1,10‐phenanthroline: synthesis,characterization, solvent‐extraction studies,catalase‐like functions and DNA cleavage abilities

A series of homo‐, heterodinuclear and homotrinuclear copper(II) complexes containing a new Schiff base ligand and 1,10‐phenanthroline were synthesized. Based on results of elemental analyses, FTIR, ¹H‐ and ¹³C‐NMR spectra, conductivity measurements and magnetic susceptibility measurements, the complexes had general compositions {[Cu(L)(H₂O)M(phen)₂](ClO₄)₂ [M = Cu(II), Mn(II), Co(II)]} and {[Cu₃(L)₂(H₂O)₂](ClO₄)₂}. The metal:L:phen ratio is 2:1:2 for the dinuclear copper(II) complexes and the metal:L ratio was 3:2 for the trinuclear copper(II) complex. The liquid–liquid extraction of various transition metal cations [Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II), Hg(II)] from the aqueous phase to the organic phase was carried out using the diimine–dioxime ligand. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) from the aqueous phase to the organic phase. Furthermore, catalytic activitiy of the complexes for the disproportionation of hydrogen peroxide was also investigated in the presence of imidazole. Dinuclear copper(II)–manganese(II) complex has some similarity to manganese catalase in structure and activity. The interaction between these complexes and DNA has also been investigated by agarose gel electrophoresis; we found that the homo‐ and heterodinuclear copper complexes can cleave supercoiled pBR322 DNA to nicked and linear forms in the presence of H₂O₂. Copyright © 2009 John Wiley & Sons, Ltd.     

Reaction of ammonium chloride with the copper(II) sulfide and oxide,and identification of the reaction products

The processes and products of the reaction of copper(II) sulfide and oxide with ammonium chloride were studied. The process of the copper(II) compounds hydrochlorination was investigated with thermogravimetry and kinetic studies. Reaction products were studied by infrared spectroscopy and X-ray phase analysis.     

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 (0.01-6M), 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.     

Solvent extraction of arsenic(V) with dispersed ultrafine magnetite particles.

The solvent extraction of arsenic(V) was investigated using heptane containing ultrafine magnetite particles and hydrophobic ammonium salt. Arsenic(V) was favorably extracted from aqueous solutions of pH ranging over 2-7, where the distribution ratio (10(3)) was independent of the pH. Although the addition of alkyl ammonium salt improved the phase separation, no notable influence was observed on the extraction of arsenic(V). Oleic acid suppressed the distribution ratio of arsenic(V) when the concentration exceeded 10(-2) M. Sulfate did not interfere with the extraction, while the presence of more than 10(-3) M phosphate decreased the distribution ratio. Metal cations including calcium(II), manganese(II), cobalt(II), nickel(II), copper(II), zinc(II) and lanthanum(III) did not give any serious interference up to the 10(-4) M level. According to equilibrium and kinetic studies, the extraction of arsenic(V) can be interpreted by the adsorption of H2AsO4- onto the surface of dispersed magnetite particles. The relationship between the amount of arsenic(V) extracted in the organic phase and that remaining in an aqueous phase followed a Langmuir-type equilibrium equation. The maximum uptake capacity was determined to be 4.8 x 10(-4) mol/g-magnetite (36 mg As/g). The arsenic(V) extracted in the organic phase was quantitatively recovered by back-extraction with an alkaline solution.     

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

Summary 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.     

On-line sequential injection dispersive liquid-liquid microextraction system for flame atomic absorption spectrometric determination of copper and lead in water samples

A simple, sensitive and powerful on-line sequential injection (SI) dispersive liquid-liquid microextraction (DLLME) system was developed as an alternative approach for on-line metal preconcentration and separation, using extraction solvent at microlitre volume. The potentials of this novel schema, coupled to flame atomic absorption spectrometry (FAAS), were demonstrated for trace copper and lead determination in water samples. The stream of methanol (disperser solvent) containing 2.0% (v/v) xylene (extraction solvent) and 0.3% (m/v) ammonium diethyldithiophosphate (chelating agent) was merged on-line with the stream of sample (aqueous phase), resulting a cloudy mixture, which was consisted of fine droplets of the extraction solvent dispersed entirely into the aqueous phase. By this continuous process, metal chelating complexes were formed and extracted into the fine droplets of the extraction solvent. The hydrophobic droplets of organic phase were retained into a microcolumn packed with PTFE-turnings. A portion of 300 μL isobutylmethylketone was used for quantitative elution of the analytes, which transported directly to the nebulizer of FAAS. All the critical parameters of the system such as type of extraction solvent, flow-rate of disperser and sample, extraction time as well as the chemical parameters were studied. Under the optimum conditions the enhancement factor for copper and lead was 560 and 265, respectively. For copper, the detection limit and the precision (R.S.D.) were 0.04 μg L⁻¹ and 2.1% at 2.0 μg L⁻¹ Cu(II), respectively, while for lead were 0.54 μg L⁻¹ and 1.9% at 30.0 μg L⁻¹ Pb(II), respectively. The developed method was evaluated by analyzing certified reference material and applied successfully to the analysis of environmental water samples.     

The Study of Indirect Determination of Tiopronin by Extraction Flotation Copper(II) with an Ammonium Sulfate‐Water‐n‐Propyl Alcohol System

A novel method for indirect determination of tiopronin by extraction flotation of copper(II) with an ammonium sulfate‐water‐n‐propyl alcohol system was developed. The effects of different parameters, such as acidity, the amount of NH₄SCN and various salts on the flotation yield of Cu(II), have been studied to optimize the experimental conditions. Under the optimum conditions, Cu(II) is reduced to Cu(I) by tiopronin, and the resulting Cu(I) can react with SCN^? to form a white emulsion precipitate CuSCN. In the presence of (NH₄)₂SO₄, the mixture consisting of n‐propyl alcohol and water can be separated into an n‐propyl alcohol phase and a water phase. In the process of phase separation of n‐propyl alcohol from water, the precipitated CuSCN is extracted and stays in the interface of n‐propyl alcohol and water. The amount of tiopronin can be determined by measuring the flotation yield of Cu(II). The detection limit is 0.32 mg L^?1 and the linear range is maintained in the range of 0.40±13.0 mg L^?1 with a correlation coefficient of 0.9991. This proposed method has been successfully applied to the determination of tiopronin in tablets, urine and human plasma with satisfactory results.     

Synthesis, characterization and structure effects on extractability and selectivity of N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane towards some divalent cations

The extraction of copper(II), nickel(II) and cobalt(II) from the aqueous phase with N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane (MAS), which was synthesized from 1,4-bis(m-aminophenoxy)butane and salicylaldehyde, was studied. Microanalytical data, elemental analysis, UV-visible 1H and 13C n.m.r. spectra and IR-spectra were used to confirm the structures. The extractability and selectivity of divalent cations were evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. Cu+2 showed the highest extractability and selectivity at pH 6.0, whereas Ni+2 and Co+2 showed at pH 9.2. The stoichiometries of the compounds formed were estimated to be CuL, CoL, NiL, where L is N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane. It was concluded that MAS can effectively be used in solvent extraction of copper(II), nickel(II) and cobalt(II) from the aqeous phase to the organic phase.     

Reactions of Oxides of Some 3d Elements with Ammonium Hydrogen Difluoride

Reactions of iron, manganese(II), manganese(IV), copper, and zinc oxides with ammonium hydrogen difluoride were studied by thermogravimetry, X-ray phase analysis, IR spectrometry, and chemical analysis.     

Liquid chromatographic determination of cobalt(II), copper(II) and iron(II) using 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone as derivatizing reagent

The complexing reagent 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone (TAPT) was examined for high performance liquid chromatographic (HPLC) separations of cobalt(II), copper(II) and iron(II) or cobalt(II), nickel(II), iron(II), copper(II) and mercury(II) as metal chelates on a Microsorb C-18, 5-mum column (150x4.6 mm i.d.) (Rainin Instruments Woburn, MA, USA). The complexes were eluted isocratically with methanol:acetonitrile:water containing sodium acetate and tetrabutyl ammonium bromide (TBA). UV detection was at 254 nm. The solvent extraction procedure was developed for simultaneous determination of the metals, with detection limits within 0.5-2.5 mug ml(-1) in the final solution. The method was applied for the determination of copper, cobalt and iron in pharmaceutical preparation.     

Extraction of copper(II) with N-(para-tert-butylbenzoyl)-N′,N′-dialkylhydrazines

Extraction of Cu(II), Co(II), Ni(II), and Zn(II) with N-(para-tert-butylbenzoyl)-N??,N??-dialkylhydrazines was studied. In contrast to other listed elements, copper(II) is extracted with these reagents in a wide pH range and NH₃ concentrations, which provides its selective separation. Effect of chain length of the N??,N??-alkyl groups and solvent nature on copper extraction and its stripping conditions were determined. Extraction constants were calculated. Ammonium salts decrease the extraction degree of copper(II). The studied reagents are superior to the known industrial reagent of ??-diketone class, LIX 54, in terms of copper(II) extraction efficiency from ammonia media.     

Liquid-liquid extraction of copper (I) and copper (II) as ion-paired complexes with acyclic 2-thienyl-containing polythioether and triphenylmethane dye anion

Three acyclic polythioethers containing 2-thienyl units at both ends were synthesized and the effect of substituent on the extraction of copper(II) was studied. The methyl groups in the terminal thiophene ring have imparted an appreciable degree of increase in the percent extraction of copper(II), while the introduction of chlorine atoms into the 2-thienyl unit resulted in the reverse effect. Among the counter dye anions examined, tetrabromophenolphthalein ethylester was the best one for copper(II) extraction. The composition of extracted species was evaluated to be 122 (Cu(II)/polythioether/dye anion). Quantitative extraction of copper(I) was attained as complexes with various triphenylmethane dyes, i.e., bromocresol green, bromothymol blue, bromo-phenol blue and pyrogallol red. Copper(I) in organic phase was completely back-extracted with 2 mole/l sulfuric acid containing 10% hydrogen peroxide.     

Activated carbon cloth filled pipette tip for solid phase extraction of nickel(II), lead(II), cadmium(II), copper(II) and cobalt(II) as 1,3,4-thiadiazole-2,5-dithiol chelates for ultra-trace detection by FAAS

A solid phase extraction method is established for preconcentration of nickel, lead, cadmium, copper and cobalt using pipette tip solid phase extraction. The presented process was dependent on chelation of analytes with 1,3,4-thiadiazole-2,5-dithiol, then allowing the solution to flow through an activated carbon cloth packed pipette tip. The adsorbed metal chelates on the surface of activated carbon cloth were eluted by 5 mL of 3 M HNO₃. The concentrations of nickel, lead, cadmium, copper and cobalt were detected using a flame atomic absorption spectrometer (FAAS). The pipette tip solid phase extraction exhibit a preconcentration factor of 120. The limit of detection values were 2.7, 1.7, 1.3, 2.0 and 2.9 µg L^?1 for Ni(II), Pb(II), Cd(II), Cu(II) and Co(II), respectively. Validation of the method was checked by the analysis of TMDA-53.3 and TMDA-64.2 certified reference materials. The method was successfully applied for water and fertiliser samples.     

Extraction of copper(II) with the APCD/DIBK system from concentrated hydrochloric and nitric acid media: estimation of true limit of acidity for the extraction

The extraction of copper(II) from strongly acidic solution (0.01-8M hydrochloric and 0.01-5M nitric acid) with ammonium 1-pyrrolidinecarbodithioate in di-isobutyl ketone has been studied. Compared with the hydrochloric acid system, a considerably larger amount of the reagent is needed for complete extraction of copper chelate from nitric acid solution as the extract is more unstable in the nitric acid system. The decomposition of copper chelates extracted from nitric acid is based on the oxidation of the reagent and the chelate; the spectral change of the extract from nitric acid suggests that the copper(II) chelate is initially oxidized to copper(II) and then decomposes. The upper limit of the acidity of both acids from which the copper chelate can be quantitatively extracted strongly depends on the reagent concentration; the limit with 8 x 10(-2)M APCD (500-fold reagent: metal molar ratio) was taken as 8 and 4M for hydrochloric and nitric acid, respectively.     

Separation and determination of metals as complexes of 1-nitroso-2-naphthol-6-suiphonic and 2-nitroso-1-naphthol-6-sulphonic acids. II. Liquid chromatography on c18 bonded and copolymer stationary phases

An ion-pair Chromatographic system for the separation of copper(II), palladium(II), iron(III) and cobalt(III) as ion-associates of their l-nitroso-2-naphthol-6-sulphonate and 2-nitroso-l-naphthol-6-sulphonate anionic complexes with organic ammonium compounds and inorganic cations has been studied. Isocratic and gradient elution methods were used, and the effects of column material, organic and aqueous modifiers, and pH of the eluent on the retention were examined. The elution time for the metal complex anions depends on the eluent, the proportion of organic solvent in the mobile phase, the pH of the eluent and the extraction coefficient of the compounds. The compounds were identified photometrically with a diode-array detector at wavelengths of 229, 254, 260, 298, 320 and 400 nm. The detection limits for the metals are at the ng/ml level.     

Synergic solvent extraction of divalent cations with decafluoroheptanedione and di-n-butylsulfoxide

The synergic solvent extraction of iron(II), cobalt(II), nickel(II) and lead(II) with l,l,l,2,2,6,6,7,7,7-decafluoro-3,5-heptanedione(H(FHD)) and di-n-butylsulfoxide (DBSO), is described. The divalent cations are extracted with 99.9% efficiency at pH 5.5 in extraction times of less than 15 min. The extracted species was shown to be M(FHD)₂·2 DBSO by mass action studies and elemental analyses. The extraction of copper(II) was also studied. No DBSO adduct was found in the copper extraction.     

Investigation of bis(carboxymethyl)dithiocarbamate complexes by the extraction method

The extraction of copper, lead, cadmium, nickel and zinc dithizonates was investigated in the presence of ammonium bis(carboxy-methyl)dithiocarbamate. For all metals studied, except zinc, masking of extraction was observed, depending on the amount of the dithio-carbamate in the aqueous phase. From the shift of the pH(1 2 ) values for dithizonate extraction, the stability constants beta(2) for the metal complexes with bis(carboxymethyl)dithiocarbamate were calculated. The logarithms of the constants are 21.46, 15.45,11.24 and 7.93 for the copper, lead, cadmium and nickel complexes respectively.     

Separation of Iron(III) with Ammonium Thiocyanate‐H2O‐n‐Propyl Alcohol Extraction System in the Presence of Sodium Chloride

The behavior and conditions of liquid‐liquid extraction‐separation of Fe(III) by ammonium thiocyanate‐H₂O‐n‐propyl alcohol system in the presence of NaCl were studied, and the possible reactive mechanism of extraction of Fe(III) was deduced. The study showed that, in the presence of a given amount of NaCl, phases were separated thoroughly between n‐propyl alcohol and water. In the process of phase separation, the complex [Fe(SCN)_n]^(3‐n) formed by NH₄SCN and Fe(III) was quantitatively extracted into the n‐propyl alcohol phase. The extracted Fe(III) exists in the n‐propyl alcohol phase mainly as the forms of Fe(SCN)₂⁺ and Fe(SCN)₃. Also, the relationship between extraction yield of Fe(III) and the amount of NH₄SCN agreed well with the quadratic equation E = 0.54 + 58.14x ? 8.39x² (E and x represent the recovery rate of Fe(III) and the volume (mL) of 0.1 M NH₄SCN respectively). The quadratic R‐Square is 0.9990. With this method, Fe(III) can be completely separated from Co(II), Ni(II), Mn(II), Al(III), Bi(III) and Cd(II) at pH 1.0?2.0. The present method was applied in determining Fe(III) in samples with satisfactory results such as relative standard deviation from 2.06% to 2.89% and recovery rate in the range of 98.4?101.4%.