Abstract: A series of TiO2/bentonite catalysts (with different loadings and calcined at different temperatures) were prepared by sol-gel method. The prepared catalysts were employed to photocatalytically degrade organic dye Rhodamine B (RhB) under UV irradiation. The capabilities to degrade organic pollutants were studied by detecting the change of their absorbance and chemical oxygen demand (COD) under UV light irradiation. The results showed that they had a better catalytic reactivity when the loading was 50% and calcination temperature was 400 ℃ (Ti400). Their minerialization activity was slightly less than P25, when UV light irradiation time was 4 h, COD changes of P25 and TiO2/bentonite calcinated at 400 ℃ were 99.7% and 97.0%, respectively. But they were easier to be reused. Ti400 catalyst was employed to degrade RhB, and its photocatalytic activity was kept almost the same after recycling 7 times. The catalysts were further characterized by XRD, BET, and UV-Vis DRS. The experimental results showed that they would have a better activity when their BET surface area was larger.

Key words: TiO2/bentonite catalysts, Rhodamine B, Photocatalytic degradation, XRD, BET, UV-Vis DRS