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1

Separation of palladium(II) from mixtures of non-ferrous metal ions by solvent extraction

Radzyminska-Lenarcik E., Witt K.

Challenges of Modern Technology

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2016

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Vol. 7, no. 1

17-22

EN

The possibility of Pd(II) ions separation from mixtures of Co(II), Ni(II), Cu(II) and Pd(II) ions by solvent extraction was studied, using 1-hexyl-2methylimidazole in chloroform as the extractant. The initial concentration of each ion was 10 mM. The tests were carried out at a temperature of 25°C, at a constant strength of the aqueous solution of I = 0.5, as maintained by the KCl solution. It was demonstrated that differences in the stability and structure of their coordination sphere as well as solubility of complexes with the extractant could be used for separating the Co(II), Ni(II), Cu(II) and Pd(II) ions by solvent extraction. Pd(II), which forms flat-square complexes in the solutions, passes easily into the organic phase and is easier separated from the mixture of Co(II), Ni(II), Cu(II) ions, which form octahedral or tetrahedral complexes. Extraction percentages were calculated. For the respective metals, their values increase for increasing concentrations of the extractant in the aqueous phase. The extraction percentage decreases in the following order: Pd(II) > Cu(II) > Co(II) > Ni(II). In the case of the quaternary mixture, the highest extraction percentage for Pd(II) (70%) was obtained at a pH=7.33. Separation coefficients were also calculated. The highest separation coefficients were obtained for the system: Pd(II)/Ni(II), Pd(II)/Co(II); at a pH of 5.4 for an aqueous solution, their values are 13.3 and 7.7, respectively.

2

Removal of palladium(II) from aqueous chloride solutions with cyphos phosphonium ionic liquids as metal ion carriers for liquid-liquid extraction and transport across polymer inclusion membranes

Regel-Rosocka M., Rzelewska M., Baczynska M., Janus M., Wisniewski M.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 2

621--631

EN

This paper presents an application of three phosphonium ionic liquids for removal of Pd(II) ions from aqueous chloride solutions with liquid-liquid extraction and transport across polymer inclusion membranes (PIM). Trihexyl(tetradecyl)phosphonium chloride and bromide (Cyphos IL 101 and 102) and bis-(2,4,4-trimethylpentyl)phosphinate (Cyphos IL 104) were investigated as carriers of Pd(II) from aqueous chloride media. Extraction of Pd(II) with Cyphos IL 102 has not been previously described in the literature. Cyphos IL 102 used for the first time as metal ion carrier, efficiently extracts palladium(II) ions both with liquid-liquid extraction and PIM. NaCl concentration does not affect Pd(II) extraction with Cyphos IL 102, while increasing HCl content in the feed aqueous phase causes decrease in extraction efficiency. Stripping of Pd(II) with 0.5 M NH4OH is efficient (84 to 90%) and the organic phase after stripping could be reused for extraction. For PIM transport the highest values of the normalized initial flux are obtained for CTA membrane containing Cyphos IL 101 and a receiving phase: mixture 0.1 thiourea + 0.5 M HCl. It is indicated that initial flux does not determine the final result of the transport through the membranes because from the separation point of view, the most important is a complete transport of the solute to the receiving phase, described by the Pd(II) recovery factor.

3

Comparison of Varion resins selectivity towards palladium(II) ions in hydrochloric acid solutions with sodium chloride addition

Wołowicz A., Hubicki Z., Greluk M., Wawrzkiewicz M.

Challenges of Modern Technology

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2011

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Vol. 2, no. 3

34--37

EN

Ion exchange is Ion exchange is found more and more signifi cant importance in metal processing, and hydrometallurgy in general, not only for the removal of impurities but also for the reconcentration process of metal ions. The ion exchange method (dynamic method) was applied in the preconcentration of palladium(II) ions from the chloride solutions with sodium chloride addition. Varion resins such as the strongly basic anion exchange resins: Varion ADM and Varion ATM and the weakly basic anion exchange resin Varion ADAM were taken into account during the sorption process. The selectivity series were obtained based on the breakthrough curves of palladium(II) ions determined by means of dynamic method. Moreover, the distribution coefficients: weight and bed as well as the working anion exchange capacities were calculated. From the Varion resins — Varion ADAM is the most promising in the preconcentration of Pd(II).

4

A Bimetallic Palladium(II) Catalyzed Synthesis of 1,2-Dibromo Compounds

Qaseer H.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 1

31-38

EN

A bimetallic palladium(II) catalyst containing a triketone ligand and a bridging dinitrogen ligand oxidizes aromatic and cyclic aliphatic olefins in bromide-containing aqueous-THF to 1,2-dibromo compounds and bromohydrins. With aromatic olefins, the 1,2-dibromo products were obtained in a 70–80% yield and the bromohydrins in a 10–15% yield; this observation is opposition to that obtained in chloride containing medium where the chlorohydrin product predominates. The oxidation of 2,3-dihydrofuran gave trans-2,3-dibromotetrahydrofuran, 3-oxotetrahydrofuran, and 3-bromo-2- hydroxytetrahydrofuran in relative yields of 75%, 15%, and 10%, respectively. On the other hand, the oxidation of cyclopentene and cyclohexene affords only trans-1,2- dibromo products in about 90% yield. The stereochemistry is consistent with an anti-attack of bromide followed by decomposition involving attack of bromide from the coordination sphere of the Pd(II). The procedure outlin

5

Electrochemical Behaviour of Chloride and Bromide Complexes of Palladium(II) with 4-Amino-6-methyl-3-thio-3,4-dihydro-1,2,4-triazin-5(2H)-one in Dimethylformamide at Glassy Carbon Electrode

Fotouhi L., Ghassemzadeh M., Heravi M. M.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 7

895-902

EN

The electrochemical behaviour of palladium(II) complexes of PdCl2L(I) and PdBr2L(II) (L = 4-amino-6-methyl-3-thio-3,4-dihydro-1,2,4-triazin-5(2H)-one) has been investigated in dimethylformamide at glassy carbon electrode. Under cyclic voltammetric conditions, complex PdCl2L is found to undergo a one-electron oxidation at 1.27 V with a prewave, which is similar to oxidation of ligand L. The oxidation of ligand shows an oxidation wave at 1.25 V with EC mechanism. In the chemical reaction following the one electron irreversible oxidation of ligand, the electrochemical-generated cation radical forms a dimer, which is reduced at reverse scan at -0.66 V to reproduce the monomer. Thus, the nature of oxidation of both complexes I and II suggests a ligand-centered oxidation, because their oxidation behaviour is similar to oxidation of ligand L. However, the reduction of both complexes I and II shows a reduction peak at -1.31 V and -1.33 V respectively, which is related to reduction of metal center of complexes, Pd (II) to Pd (I).

6

Synthesis, Characterization and Magnetism of Fe(II)-Pd(II0-Fe(II) Heterotrinuclear Complexes Bridged by Dioximato Groups

Li Y., Yan C. -W., Zeng X.-C.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 5

645-652

EN

Three new Fe(II)-Pd(II)-Fe(II) heterotrinuclear complexes with dioximato-bridge have been synthesized and identified as [Fe2Pd(_-FD)2(Me2-bpy)4]SO4 (1), [Fe2Pd(_-FD)2(Me2-phen)4]SO4 (2) and [Fe2Pd(_-FD)2(Me-phen)4]SO4 (3); where (_-FD)2_ represents _-furildioximato; Me2-bpy, Me2-phen and Me-phen denote 4,4_-dimethyl-2,2_-bipyridine; 2,9-dimethyl-1,10-phenanthroline (Me2-phen) and 5-methyl-1,10-phenanthroline (Me-phen). Based on elemental analyses, molar conductance measurements, IR and electronic spectral studies, these complexes are proposed to have extended dioximato-bridged structures and to consist of two iron(II) ions and a palladium(II) ion, in which the central palladium(II) ion has a square-planar environment and the end capped two iron(II) ions have a distorted octahedral environment. The magnetic properties of complexes [Fe2Pd(_-FD)2(Me2-bpy)4]SO4 (1) and [Fe2Pd(_-FD)2(Me2-phen)4]SO4 (2) were investigated over the 4.2~300Krange and correspond to what is expected for an antiferromagnetic Fe(II)-Fe(II) pair with SFe(II) = 2 and SPd(II) = 0 (Pd2+ is a diamagnetic in a square-planar environment) local spins. The exchange integral (J) was evaluated as J = _2.89 for (1) and J = _3.16 for (2) based on the spin Hamiltonian operator, _ _ _ H = JS S 1 2 _ _ 2 .

7

Spektrofotometryczna nowa metoda oznaczania palladu(II) za pomocą 6-tioksantyny

Sikorska-Tomicka H., Regulska E.

Zeszyty Naukowe Politechniki Białostockiej. Matematyka, Fizyka, Chemia

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1998

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Z. 18

73-81

PL

Opracowano nową metodę oznaczania palladu(II) z zastosowaniem 6-tioksantyny. Oznaczono pallad(II) w zakresie stężenia od 2,0 do 20 mg/cm3 przy optymalnym pH 1,0 - 2,2. Badano wpływ obcych jonów na wyniki oznaczania palladu(II). Ustalono skład tworzenia się kompleksu Pd-TX, który wynosi 4 : 1. Opracowaną metodą oznaczono pallad(II) w katalizatorze palladowym.

EN

A new method for determinatin of palladium(II) with thioxantine has been developed. The determination range of palladium(II) is 2,0 - 20 mg/cm3 at optimal range pH 1,0 - 2,2. The effects of substances and ions on the results of the determination was evaluated. The molar ratio of palladium(II) with tioxantine is 1 : 4. Described method was used for the determination of palladium(II) in catalyst.

8

Spektrofotometryczna nowa metoda oznaczania palladu(II) za pomocą 6-tiopuryny

Sikorska-Tomicka H., Sobolewska H.

Zeszyty Naukowe Politechniki Białostockiej. Matematyka, Fizyka, Chemia

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1998

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Z. 18

65-72

PL

Opracowano nową metodę oznaczania palladu(II) z zastosowaniem 6-tiopuryny. Oznaczono pallad(II) w zakresie stężenia od 1,0 - 10 mg/cm3 przy optymalnym pH 1,0 - 2,0. Badano wpływ obcych jonów na wyniki oznaczania palladu(II). Ustalono skład tworzącego się kompleksu Pd : TP = 2 : 3.

EN

The reaction of 6-thiopurine (TP) with palladium(II) has been applied in spectrophotometric determination of palladium(II). The determination range of palladium is 1,0 - 10 mg/cm3 at optimal pH 1,0 - 2,0. The efects of substance and ions on the results of the determination was evalued. The molar ratio of reaction palladium with 6-thiopurine is 3 : 2.

9

Spektrofotometryczna nowa metoda oznaczania palladu(II) za pomocą 6-tioguaniny

Sikorska-Tomicka H., Filipiuk D.

Zeszyty Naukowe Politechniki Białostockiej. Matematyka, Fizyka, Chemia

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1998

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Z. 18

83-90

PL

Opracowano nową metodę oznaczania palladu(II) z zastosowaniem 6-tioguaniny. Oznaczono pallad(II) w zakresie stężenia od 1,0 - 8 mg/cm3 przy pH od 1,0 - 2,0. Badano wpływ obcych jonów na wyniki oznaczania palladu(II). Ustalono skład tworzącego się kompleksu Pd-TG, który wynosi 1 : 2. Opracowaną metodą oznaczono pallad(II) w katalizatorze palladowym.

EN

The reaction of 6-thioguanine (TG) with palladium(II) has been applied in spectrophotometric determination of palladium(II) in a concentration range 1,0 - 8,0 mg/cm3 at optimal range pH 1,0 - 2,0. The effects of substances and ions on the results of the determination was evaluated. The molar ratio of palladium(II) with thioguanine is 1 : 2. The method was used for the determination of palladium(II) in catalyst.