Degradation of Acid Red 14 in contaminated water by Ag-SiO₂ nanocomposite

Abstract

<span style="font-size:11.0pt;font-family: " times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">An aerogel of silica gel doped with 12 wt% Ag has been prepared by an alkoxide sol-gel method with tetraethyl orthosilicate as precursor material, and calcined at 500 °C to produce nanoparticle solids. This nanomaterial has been characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller data. The nanosized silver-silica gel mixed oxide has been tested for the oxidation of the azo dye, Acid Red 14, using peroxidisulfate as oxidant. The 12 wt% Ag loaded SiO₂ shows very good efficiency in degradation of the dye. The effects of various parameters including solution <i>p</i>H, catalyst, oxidant and initial dye concentrations on degradation have been investigated and the optimum conditions determined. The catalyst is resistant to leaching and can be recycled several times without appreciable loss of activity.</span>