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Tyszczuk-Rotko K.,Maria Curie Sklodowska University | Maj J.,Fertilizer Research Institute
Electroanalysis | Year: 2012

For the first time an in situ plated lead film electrode was applied to adsorptive stripping voltammetry at relatively strong acidic conditions of, e.g., pH2. As an example of the application of such electrode a procedure for ultratrace W(VI) determination by adsorptive stripping voltammetry was elaborated. The procedure is based on the preconcentration of the W(VI)-Alizarin Red S complex at an in situ plated lead film electrode held at -0.575V (vs. Ag/AgCl), followed by a negatively sweeping square wave voltammetric scan. The proposed voltammetric procedure was applied to W(VI) determination in natural water samples. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Kowalik P.,Fertilizer Research Institute | Prochniak W.,Fertilizer Research Institute | Konkol M.,Fertilizer Research Institute | Borowiecki T.,Maria Curie Sklodowska University
Applied Catalysis A: General | Year: 2012

The effects of cesium doping (in the concentration range up to 5 wt.% Cs 2O) introduced into a copper catalyst with the composition corresponding to that for the industrial catalysts used for low-temperature water-gas shift process (LT-WGS) have been investigated. Precursors and catalysts have been characterized by XRD, ICP-OS, TPD-EGA, N 2O chemisorption, TPR, N 2 physisorption and reaction rates for WGS and methanol synthesis under the pressure of 2.5 MPa have been determined. The results reveal that the cesium doping inhibits radically methanol synthesis, with the optimal Cs 2O content being <1 wt.%. © 2011 Elsevier Ltd. All rights reserved. Source

Wolowicz A.,Maria Curie Sklodowska University | Hubicki Z.,Maria Curie Sklodowska University | Hubicki Z.,Fertilizer Research Institute
Chemical Engineering Journal | Year: 2012

A chelating resin of a new generation with the bis-picolylamine functional groups namely Lewatit MonoPlus TP-220 was applied in selected noble metal recovery such as palladium(II), platinum(IV), gold(III) and base metals such as Cu(II), Co(II), Ni(II) and Zn(II). Characterization of the ion exchanger including the contents of H, C and N atoms and the type of functional groups was carried out using the elementary analysis and FT-IR methods. Surface morphology (AFM and SEM pictures) of the commercially available Lewatit MonoPlus TP-220 resin was presented. Based on the batch method it was found that Lewatit MonoPlus TP-220 removed palladium(II), platinum(IV), gold(III) and cooper(II) form acidic solution very efficiently whereas zinc(II), nickel(II) and cobalt(II) to a smaller extend but the resin shows negligible higher selectivity for palladium(II) ions compared to others. The series can be presented as follows: Pd(II) > Au(III) > Pt(IV) > Cu(II) > Zn(II) > Co(II) > Ni(II). Due to this fact, the surface morphology of Lewatit MonoPlus TP-220 and the FT-IR spectrum after the Pd(II) sorption were also presented and the column studies were carried out in order to find the working ion exchange capacities for palladium(II) ions and to check how acids (nitric and hydrochloric) concentrations influence the sorption efficiency. The kinetic analysis, one of the most important factors making the metal ions removal economical and short time consuming, was discussed in this paper. © 2012 Elsevier B.V. Source

Wolowicz A.,Maria Curie Sklodowska University | Hubicki Z.,Maria Curie Sklodowska University | Hubicki Z.,Fertilizer Research Institute
Chemical Engineering Journal | Year: 2011

Weakly basic anion (WBA) exchange resins applicability in palladium(II) removal from the acidic solution systems was tested. Equilibrium experiments, kinetics, effects of phase contact time, acids and sodium chloride concentrations on Pd(II) sorption were studied by means of both batch and fix-bed column methods. In this paper the analysis of the data obtained for Amberlite IRA-92, Amberlite IRA-95, Amberlite IRA-96, Dowex 66, Varion ADAM and Lewatit MP-62 was discussed and compared to those obtained for Amberlyst A-23, Amberlyst A-24, Dowex WGR-2 and Amberlyst A-21. The sorption capacity as high as 121.48 mg/g for Varion ADAM was found. The sorption process of Pd(II) on the weakly basic anion exchange resins was fast and the sorption capacities were found to be influenced by the acids and sodium chloride addition. The studies of Pd(II) uptake using the fix-bed columns confirm the greater affinity of Varion ADAM for Pd(II) than of the other weakly basic anion exchangers. Kinetics of Pd(II) follows the pseudo-second order kinetic equation. © 2011 Elsevier B.V. Source

Wolowicz A.,Maria Curie Sklodowska University | Hubicki Z.,Maria Curie Sklodowska University | Hubicki Z.,Fertilizer Research Institute
Solvent Extraction and Ion Exchange | Year: 2010

The chelating ion exchange resin - Dowex M 4195 was used in palladium(II) complexes adsorption from the acidic solutions. This study discusses the sorption kinetics, and more specifically the interparticle diffusion behavior of palladium(II) onto Dowex M 4195. The adsorption studies were used to determine the amount of palladium(II) complexes uptake (resin loading), the distribution coefficients, and the recovery efficiency of Pd(II) complexes. The influence of the agitation speed, the beads size (mean radius of swollen particles), the palladium concentrations, as well as acid concentrations (ionic strength of solutions), the macrocomponent addition (sodium chloride), and the phases contact time was also discussed. Moreover, the effect of temperature was taken into account during the determination of the isotherms. The experimental data obtained at 100 mg/cm3 Pd(II) initial concentration were applied to the kinetic models, and the sorption parameters as well as the normal standard deviation were calculated. Moreover, the Langmuir, Freundlich, and Tempkin-Pyzhev isotherm models were applied and the isotherms parameters were calculated. © Taylor & Francis Group, LLC. Source

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