Abstract:

In order to solve the degradation problem of printing and dyeing wastewater, a homogeneous coating method was used to mix nitrogen-doped titanium dioxide powder with PET solution and then load on the polyester (PET) fabric. The photocatalytic degradation efficiency and reusability of methylene blue doped aqueous solution of nitrogen-doped titanium dioxide loaded PET fabric under sunlight irradiation were studied. The experimental results show that the nitrogen-doped titanium dioxide supported PET fabric has good photocatalytic performance. After 150 min of sunlight irradiation, the degradation rate of the methylene blue solution containing the original PET fabric is only 8.2%, while the degradation rate of the methylene blue solution with the photocatalytic polyester fabric is increased to 94.8%. The degradation rae is still above 88% after 5 washed cycles, indicating good durability of the functional layers. In addition, the experimental study shows that photocatalytic polyester fabric has higher catalytic activity in alkaline solution with pH of 9.0 and in sunny weather, while the increase of concentration of NaCl solution and methylene blue solution will inhibit the photocatalytic reaction.

Key words: nitrogen-doped titanium dioxide, photocatalytic, homogeneous coating, polyester fabric, methylene blue, printing and dyeing wastewater