Enhanced sorption capacity of a metal-dye system from water effluents by using activated industrial waste.

Activated coal fly ash (FA) treated with NaOH and hexadecyltrimethylammonium bromide (HDTMABr) was used as adsorbent for removal of cadmium(II) ions and rhodamine B (RB) from an aqueous solution. Characterization of fly ash and FA-HDTMABr were done using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The sorption equilibrium in the system was analysed using isotherm models, such as Freundlich, Langmuir, generalized Langmuir-Freundlich, Redlich-Peterson, Jovanović, extended Jovanović, Tóth, Frumkin-Fowler-Guggenheim, Fowler-Guggenheim-Jovanović-Freundlich, Temkin, Dubinin-Radushkevich, Halsey, Brunauer, Emmett and Teller.

Characterisation and utilisation of solid waste from coal combustion to modelling of sorption equilibrium in a bi-component system metal-dye.

It was found that the chemical enhancement of fly ash from coal combustion by tetrabutylammonium bromide treatment yields an effective and economically feasible material for the treatment of chromium and basic dye Rhodamine B containing effluents. Characterisation of coal fly ash and treatment with tetrabutylammonium bromide were done by using a Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, confocal three-dimensional microscope, X-ray diffraction and laser particle sizer. The studies of equilibrium in a bi-component system by means of extended Langmuir, extended Langmuir-Freundlich and Jain-Snoeyink models were analysed.

Syntheses, crystal structures and antioxidant study of Zn(II) complexes with morin-5'-sulfonic acid (MSA).

The study of modified synthetic procedure of water soluble morin-5'-sulfonic acid sodium salt (NaMSA) involving less aggressive chemicals and carried out at mild conditions was described. The NaMSA salt is a convenient source of anionic morin-5'-sulfonic ligand (MSA) in ion exchange reactions. The coordination ability of MSA ligand towards the zinc cations was investigated in aqueous solution and in solid state.

Tautomeric and Microscopic Protonation Equilibria of Anthranilic Acid and Its Derivatives.

The acid-base chemistry of three zwitterionic compounds, namely anthranilic (2-aminobenzoic acid), -methylanthranilic and -phenylanthranilic acid has been characterized in terms of the macroconstants , , the isoelectric point p, the tautomerization constant and microconstants , , , . The potentiometric titration method was used to determine the macrodissociation constants. Due to the very poor water solubility of -phenylanthranilic acid the dissociation constants p and p were determined in MDM-water mixtures [MDM is a co-solvent mixture, consisting of equal volumes of methanol (MeOH), dioxane and acetonitrile (MeCN)].

Studies on equilibrium of anthranilic acid in aqueous solutions and in two-phase systems: aromatic solvent-water.

The acid-base equilibria of anthranilic acid have been characterized in terms of macro- and microdissociation constants (dissociation constants K(a1), K(a2) and tautomeric constant K(z)). On the basis of spectrophotometric investigations the values of the distribution ratio D of anthranilic acid in the two-phase systems: aromatic solvent (benzene, ethylbenzene, toluene, chlorobenzene, bromobenzene)-aqueous solution were obtained. Employing the results of potentiometric titration in the two-phase systems: aromatic solvent-aqueous solution the distribution constant K(D) and dimerization constant K(dim) values were calculated.

Studies on the distribution of N-phenylanthranilic acid in two-phase system: Aromatic solvent-water.

The detailed description of equilibria of N-phenylanthranilic acid in the aqueous solutions and in the two-phase systems: aromatic solvent-aqueous solution were obtained. The isoelectric point, pH(I), the dissociation constants of the protonated form, K(a1), and the neutral form, K(a2), in the aqueous solutions were determined from the apparent ionization constant in methanol-water solutions of various proportions by extrapolation to zero co-solvent using Yasuda-Shedlovsky procedure. On the basis of the spectrophotometric investigations, the values of the distribution ratio, D, of N-phenylanthranilic acid in the two-phase systems: aromatic solvent (benzene, ethylbenzene, toluene, chlorobenzene, bromobenzene)-aqueous solution were obtained.

Investigations of sequential leaching behaviour of Cu and Zn from coal fly ash and their mobility in environmental conditions.

The quantitative evaluation of chemical fraction of Cu and Zn in the coal fly ash by methods of five-step sequential extraction was carried out in order to characterize metal mobility in environmental conditions. The research involved (i) water-soluble (pH 7), (ii) acid-soluble (pH 5), (iii) oxide, (iv) difficult reducible and (v) residual metal fractions. It was discovered, that the total extraction of the studied metals from coal fly ash to solutions take place in the following quantities Cu-39.

Investigations of chemical fraction of Co and Ni in industrial fly ash and mobility of metals in environmental conditions.

The quantitative evaluation of chemical fraction of Co and Ni in the industrial fly ash by methods of five step sequential extraction was carried out in order to characterize metal mobility in environmental conditions. The research involved (i) water-soluble (pH=7), (ii) acid-soluble (pH=5), (iii) oxide, (iv) sulfide and (v) residue metal fractions. It was discovered, that the total extraction of the studied metals from fly ash to solutions take place in the following quantities Co - 35.