Photocatalytic treatment of three textile dye solutions by industrial immobilized TiO2 nanoparticles

Photocatalytic treatment of the solution containing three commercial textile dyes (AO10, AO12 and AO8) has been investigated using TiO2 nanoparticles immobilized on a non-woven glass fiber fabric in a circulation photochemical reactor equipped with a 15W UV lamp. The investigated photocatalyst was industrial Millennium PC-500 (crystallites mean size 5-10 nm) immobilized on non-woven paper (Ahlstrom Research & Services). SEM images and X-ray analyses of the immobilized TiO2 nanoparticles showed that it could be regenerated and used for several times. spectra and ammonium ion formation. The dye solutions could be completely decolorized and effectively mineralized, with an average overall TOC removal larger than 90% for a photocatalytic reaction time of 6 h. The nitrogen to nitrogen double bond of the azo dyes was transformed predominantly into NH4+ ion. Photocatalytic degradation experiments of dye solutions at neutral and alkaline pHs and of the hydrolysed dyes were compared. The results indicated that the photocatalytic removal rate of the dyes was lower with the hydrolysed dye solutions in comparison with the neutral pure dye solutions. The photocatalysis efficiency was evaluated by figure-of-merit electrical energy per order (EEO).

Keywords:

TiO2 Nanoparticles , Photocatalysis , Wastewater Treatment , Azo Dye , TOC