Przedstawiono ługowanie, ekstrakcję ciecz-ciecz i ultrafiltrację micelarną jako skuteczne sposoby wydzielania takich pożądanych jonów metali, jak platynowce i kobalt z odpadowych katalizatorów samochodowych i z roztworów wodnych.
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Pulverized spent automobile catalyst was leached with acidic solns. (optionally with H₂O₂). The leachates were liq.-liq. extd. with com. org. phase-contg. complexants to remove Fe(III), Mg(II) and Zn(II) ions and to sep. them from Pt group ions present in the raffinate. Co(II) ions were also recovered by using a com. complexant. The ultrafiltration in presence of surface active agents resulted in sepn. of Co(II) ions from Zn(II) ions.
The effectiveness of nanofiltration with the use of ceramic membranes in the process of concentration and separation of fumaric acid or succinic acid from glycerol and citric acid from erythritol was evaluated. It was found that the retention of sodium salts of the acids investigated increased strongly with increasing the pH of the feed solution (depending on the degree of dissociation), while the retention degrees of di- and tricarboxylic acids, erythritol or glycerol were lower than 2%, irrespective of the initial concentration of the solution to be filtered. The results obtained showed that nanofiltration can be considered as one of the purification steps in the process of recovery of salts of organic acids from fermentation broth.
The main goal of this work was to study and compare the rate of iron(III) extraction from chloride solutions by commercial extractants: Alamine 336, TOPO and LIX 54 and their mixtures. Using the interfacial tension data, obtained for mixed systems, the values of surface mole fraction and molecular interaction parameter of extractants were estimated. Determination of the extraction rates was performed by using the Lewis-type stirred transfer cell. It was found that the extraction efficiency of extractants are changed in the following order: Alamine 336>TOPO>β-diketone. The addition of a chelating extractant to the system decreases the extraction efficiency, for example the addition of β-diketone to TOPO decreases the extraction efficiency by about 50%.
W prezentowanej pracy przedstawiono fragment badań dotyczących możliwości zastosowania techniki micelarnej ultrafiltracji do usuwania jonów Cr(IH) z roztworów wodnych. Analizowano wpływ stężenia chromu(III) w roztworze wyjściowym oraz wpływ typu i ilości surfaktantu dodanego do separowanego układu na efektywność i wydajność procesu MEUE.
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The paper presents a fragment of study on the applicability of micellar enhanced ultrafiltration technique for removal of Cr(III) ions from aqueous solution. The influence of the concentration of chromium(III) in the initial solution and the influence of the type and amount of surfactant added to the separated system on the effectiveness and efficiency of the MEUF process were analized.
The results of preliminary research on the possibility of removing of chromium(III) and copper(II) ions from micellar solutions in MEUF were described. The effectiveness of metal ions removal in the classical UF and MEUF was compared. It was confirmed that in the classical UF the retention of metal ions is small, independent of the concentration of the feed solution. The cross-flow micellar enhanced ultrafiltration experiments showed the usefulness of this method for the separation of metal ions from micellar solutions. The retention of metal ions in MEUF process is almost total in the case of the solutions of low concentration. However, for more concentrated solutions the retention is much smaller.
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Zbadano aktywność powierzchniową na granicy faz ciecz/ciecz dwóch równomolowych mieszanin binarnych typu ekstrahent/ekstrahent: Alamine 336/TOPO i D2EHPA/TOPO. Oszacowano skład mieszanej warstwy adsorpcyjnej powstającej w danym układzie binarnym na granicy faz woda/węglowodór oraz parametr oddziaływań międzycząsteczkowych bb bb b wykorzystując równanie Rosena. We wszystkich analizowanych układach mieszanych występowała współadsorpcja, natomiast zjawiska synergizmu w obniżaniu napięcia międzyfazowego nie obserwowano. Wyniki wskazują, że skład mieszanych warstw adsorpcyjnych, w których dominuje mniej aktywny powierzchniowo ekstrahent jest odmienny od składu fazy objętościowej. Na podstawie zmierzonych wartości dynamicznego napięcia międzyfazowego hydrofobowych ekstrahentów i ich równomolowych mieszanin oszacowano wartości współczynników dyfuzji D. Stwierdzono, że ekstrahent dominujący w mieszanej warstwie adsorpcyjnej decyduje o kinetyce adsorpcji w rozpatrywanych układach binarnych.
EN
Equil. and dynamic interfacial tension was detd. with a drop vol. tensiometer for equimol. trioctylphosphine oxide (I)–di-2-ethylhexylphosphoric acid (II), and equimol. I–Alamine 336 (trioctyl/decylamine as active compd.) (III) mixts. studied as extractants in the water-toluene system. From each mixt. the extractants were co-adsorbed at the water–toluene interface but they were not synergistic in suppressing the interfacial tension. The compn. of the adsorbate differed from that of the bulk phase. Adsorption kinetics was controlled by the dominating extractant. In the binaries, I was surprisingly inactive as adsorbent. The surface of the mixed adsorption monolayer was occupied in 30% by I mols. Mol. interaction parameters, adsorption free energy, Szyszkowski’s isotherm correlation coeffs., diffusion coeffs., and surface area for a statistical mol. adsorbed were detd.
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The FT-IR spectrum for two chelating metal ion extractants: 2-hydroxy-5-nonylacetophenone oxime (HNAF) and 1-phenyldecane-1,3-dion (b-diketone) and decanol used as a modifier were presented. Moreover, two equimolar binary mixtures of extractant/extractant and extractant/modifier type were considered. The interaction between two extractants or the extractant and modifier molecules adsorbed at the mixed adsorption monolayer formed in extraction systems were discussed. The usefulness of the spectral technique (FT-IR) for studying the formation of a new ligand association adducts between the extractants and modifiers or two extractants in a binary mixture as well as a formation of self-association adducts of the extractants molecules were presented.
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