Performance of self-cleaning cotton textiles coated with TiO2, TiO2-SiO2 and TiO2-SiO2-HY in removing Rhodamine B and Reactive Red 120 dyes from aqueous solutions
Salmon Landi, Joaquim Carneiro, Píer Parpot, O.S.G.P. Soares, M. Fernando R. Pereira, A. Fonseca, Isabel C. Neves
Abstract
ABSTRACT In the present study composites based on TiO 2 nanoparticles, SiO 2 and HY zeolite were synthesized by using a standard sol-gel methodology and analyzed by Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy-energy-dispersive X-ray spectroscopy techniques. The photocatalysts were impregnated on cotton textiles and their photocatalytic abilities were examined by degradation of Rhodamine B (RhB) and Reactive Red 120 (RR120) dyes in aqueous solution under similar solar irradiation. RhB removal efficiencies from cotton textiles were 87%, 72% and 50% for TiO 2 , TiO 2 -SiO 2 -HY zeolite and TiO 2 -SiO 2 composites, respectively and achieved after 3 h of light irradiation. However, for the RR120 dye, the reached result was different as the photodegradation for this dye (65% efficiency) was only observed in bare TiO 2 functionalized textile. In addition, for the treatment with TiO 2 -SiO 2 -HY zeolite, it was found that for initial alkaline conditions at pH of the RhB dye solution, the photodegradation rate decreased.