Abstract:
A series of nano TiO
2 photocatalytic dispersed solutions were prepared by using deionized water as a medium, sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (DBS), ployvinylpynolidone (PVP), cetyl trimethyl ammonium bromide (CTAB), polyacrylic acid sodium (PAAS) surfactant as the dispersant, respectively. The TiO
2 dispersed solutions were used as a finishing agent for the polyester sea-island filament needle punched nonwoven (PFN-NWF) to prepare TiO
2/PFN-NWF photocatalytic composites through the twice dip-padding technique. The morphology, structure and properties of TiO
2 solutions and TiO
2/PFN-NWF photocatalytic composites were investigated. The capsicol and formaldehyde solution was used as a model contaminant to evaluate the photocatalytic activity of the TiO
2/PFN-NWF composites. The results indicate that the dispersion system of TiO
2 significantly affected by acidity-basicity of solution and dispersant, and the dispersivity of TiO
2 solution can be effectively improved by addition of PAAS. The TiO
2 is well immobilized on the surface of PFN-NWF and has good load fastness, the load rate of TiO
2/PFN-NWF composites could be achieved 4.79%. The TiO
2/PFN-NWF composites also have excellent catalytic performance. The capsicol (2 mL) drops on the surface of TiO
2/PFN-NWF composites can be completely degraded under natural light irradiation for 60 min. The degradation ratio of formaldehyde is 95.98% under xenon lamp (300 W) irradiation for 3 h, and this ratio is remained above 90.19% after five cycles.