Abstract: In order to realize the targets of using waste into treatment of waste and turning the waste into treasure,using Ti-bearing blast furnace slag as material and MnO₂ as the modifier through high temperature solid phase method produced TiO₂ photocatalyst. Through XRD，UV-Vis diffuse analyzed its characterization，Influence of factors such as pH of the simulated waste water，addition amount of photocatalyst，and illumination time on degradation rate of Cr⁶⁺ by TiO₂ photocatalyst. Results indicated that anatase phase TiO₂ produced through calcination at 800 ℃ for 2 h of Ti-bearing blast furnace slag photocatalyst has better photo response effect to ultraviolet region. The degradation rate of Cr⁶⁺ reached to 89.17%，when simulated effluent pH was 1.62，photocatalyst additive amount was 0.40 g/L，illumination time was 60 min.

Key words: Ti-bearing blast furnace slag, Manganese modified photocatalysis, Cr6+degradation rate