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Salting-out chromatography : a practical review

Komsta Ł., Skibiński R., Bojarczuk A, Radoń M.

Acta Chromatographica

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2011

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Vol. 23, no. 2

191--203

EN

This review focuses on the salting-out effect and its use in chromatographic analysis, mainly thin-layer chromatography. First, a theoretical background is given, focusing on the general salting-out theory and a comparison with chaotropic salt addition, practised recently in reversed-phase chromatography. All the salting-out chromatographic applications in literature (from the 1960s to the present moment) are then reviewed.

2

Salt effect on the enthalpy of mixing of 2-propanol + acetic acid at 303.15 K

Tamilarasan R., Baffna S.G., Anand-Prabu A., Dharmendira-Kumar M.

Polish Journal of Chemical Technology

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2009

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Vol. 11, nr 4

20-23

EN

This paper presents the effect of two dissolved inorganic salts (zinc chloride, ZnCl2 and ammonium chloride, NH4Cl) on the enthalpy of mixing (HE) of 2-propanol + acetic acid binary system measured at 303.15 K using an isothermal displacement calorimeter with vapour space. A decreasing trend in the excess enthalpy of mixing values in the presence of ZnCl2 and NH4Cl indicate the endothermic behavior of this system. The Redlich-Kister equation has been used to fit the experimental HE data. The deviations from the ideal value and binary parameters were calculated and reported.

3

Analysis of the effect of the special food additives on rheological properties of aqueous and milk solutions

Broniarz-Press L., Różański J., Różańska S.

International Journal of Applied Mechanics and Engineering

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2005

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Vol. 10, no spec

175-181

EN

The object of the studies was to determine the effect of various additives and solvents to Na-CMC, Guar gum (two different weight-average molecular weight), Xanthan gum and Arabic gum solutions on the change of their rheological properties. The additives studied were sodium chloride and saccharose. The solvents used were water and milk. The rheological properties of Na-CMC and guar gums solutions were described by Ostwald-de Waele power-law. Xanthan gum solutions had rheological properties described by Herschel-Bulkley equation. Arabic gum was characterized by Newtonian properties for aqueous solution and shear-thinning properties for milk solutions.

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Photodehalogenation of 9,10-Dichloroanthracene Induced by Electron Transfer Fluorescence Quenching with Primary and Tertiary Amines in Acetonitrile and n-Hexane. Salt Effect on Photodechlorination Process

Mac M.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 4

427-439

EN

Quenching of 9,10-dichloroanthracene (DCA) fluorescence by primary or tertiary amines in acetonitrile solution results in formation of DCAradical anions, amine radical cations and triplet DCA, which were observed by nanosecond flash photolysis. In n-hexane, only the triplet-triplet absorption of DCA is observed. Rate constants of back electron transfer from the solvent separated radical ion pair (SSRIP), kbet, were calculated from the quantum yields of charge separation and triplet state formation by assuming a rate of 5_108 s-1 for ion separation from the SSRIP. The rate constants kbet follow the trends expected from the electron transfer theory (inverted Marcus region). Proton transfer from radical cation of primary amine to the radical anion of DCA, occurring in the contact radical ion pair (CRIP) has been found to be the decisive step for photodehalogenation in n-hexane. Importance of the heavy atom effect has been discussed on the basis of photophysical scheme, describing the processes occurring in the CRIP (SSRIP). It has been found, that lithium perchlorate catalyses the photodechlorination of DCA in acetonitrile solution, due to acceleration of the charge separation and retardation of the recombination of formed radical ion pair.

5

Effect of the strong electrolyte addition on rheological properties of aqueous solutions of sodium carboxymethyl cellulose

Broniarz-Press L., Różański J., Dryjer S., Bednarz J.

International Journal of Applied Mechanics and Engineering

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2003

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Vol. 8, no spec.

207-212

EN

The object of the studies was to determine the effect of leading of various additives to different molecular masses (Mw = 250000 and Mw = 700000) Na-CMC aqueous solutions on the change of rheological properties of these solutions. The additives studied were sodium sulphate, sodium chloride, potassium chloride, sodium carbonate, potassium ferricyanide and ferrocyanide, sodium hydroxide as potentially useful in electrochemical technique. It has been shown that the presence of salt in a solution causes the decrease of consistency index and the increase of flow behaviour index as well as leads to better stabilization of solution (what results probably from the biodegradation slowing down a polymer studied). Additionally in the solutions of this type the electrochemical process has been carried out. No effect of the passage of current on rheological properties has been observed.