Preparation of hybrid pigments via adsorption of selected food dyes onto inorganic oxides based on anatase titanium dioxide

The paper reports on a characterisation of hybrid pigments obtained via adsorption of selected food dyes onto inorganic oxides based on anatase titanium dioxide. The process of adsorption was conducted for dye concentrations varying from 10 to 50 mg/dm3. The physicochemical properties of the inorganic supports and hybrid pigments obtained were determined. Particle size distribution and surface morphology, and adsorptive as well as electrokinetic properties (zeta potential) of the above products were evaluated. The efficiency of food dye adsorption on TiO2 or TiO2–SiO2 was examined and the degree of coverage of the inorganic supports with the food dyes was also estimated from elemental analysis. The synthesised food dye/titania support hybrids can be used in pharmaceutical products.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthesis of TiO2–SiO2 oxide composite in emulsion system. ► Preparation of hybrid pigments via adsorption of food dyes onto inorganic supports. ► Evaluation of efficiency of food dyes adsorption process.