Photocatalytic Degradation of Dye C.I. Direct Blue 78 Using TiO 2 Nanoparticles Immobilized on Recycled Wool‐Based Nonwoven Material

This paper discusses the possibility of immobilization of TiO 2 nanoparticles onto recycled wool‐based nonwoven material, which can be utilized for removal of dyes from wastewater. The photocatalytic activity of TiO 2 nanoparticles deposited on the nonwoven material was evaluated in the aqueous solution of direct dye C.I. Direct Blue 78 under the UV illumination. Nonwoven material modified with TiO 2 nanoparticles provides complete removal of dye from the solution already after 4–6 h of UV illumination. However, photodegradation of the dye adsorbed on the nonwoven material was obtained within 24 h of UV illumination. The rate of dye adsorption and photodegradation depends on the amount of deposited TiO 2 nanoparticles. The increase of initial dye concentration induced decrease in photocatalytic efficiency of immobilized TiO 2 nanoparticles. The highest photodegradation rate was achieved in acidic conditions. Elevated temperatures positively affected the removal of dye from solution. Photocatalytic activity of TiO 2 nanoparticles deposited on nonwoven material was preserved after three photodegradation cycles.