Photocatalytic Degradation of Allura Red (AR) with TiO₂ Immobilized on Solution Blow Spinning (SBS) - Spun TIPP/PVP Membranes

Abstract

Titanium dioxide (TiO2) nanoparticles were immobilized on the surface of 14% TIPP/PVP membranes by (1) dip coating the membrane in the powdered nanoparticles and (2) dip coating the membranes in PAN/DMF solution containing the nanoparticles. The composite membranes were then used for the photocatalytic degradation of Allura Red (AR) dye. The effect of the presence of PAN/DMF, the initial dye concentration, and irradiation time was investigated. The extent of photocatalytic degradation was observed by measuring the absorbance of the solution using a UV-Vis spectrophotometer. The presence of PAN/DMF allowed more TiO2 nanoparticles to adhere to the surface of the membrane. The membrane with PAN/DMF/TiO2 has greater degradation efficiency across all concentrations used than the membrane without PAN/DMF. In the same membrane, the degradation efficiency increased as the initial dye concentration increased from 0.0008 mg/g AR to 0.004 mg/g AR. However, a further increase to 0.008 mg/g decreased the degradation efficiency. On the other hand, the membrane without PAN/DMF decreased its degradation efficiency as the concentration increased. The degradation efficiency increases with irradiation time but reaches equilibrium after 120 minutes. The experimental data for the membrane with PAN/DMF/TiO2 followed the Langmuir-Hinshelwood (L-H) rate form with a rate constant of 0.0253 min-1. The membrane can be reused up to 10 times at 0.0008 mg/g dye concentrations but with reduced degradation efficiency values on the extent of membrane photocatalyst reusability.