Abstract:Diatomite was pretreated by roasting, pickling and other processes, and TiO2/diatomite composite was prepared by sol-gel method with modified diatomite and butyl titanate as precursor. The composite was analyzed and characterized by XRD, SEM, FT-IR and TG, and methyl orange was used as the degradation object to investigate its photocatalytic performance. The results show that the surface of diatomite is uniformly loaded with anatase type titanium dioxide, the grain size is 35.76 nm. TiO2/diatomite composites prepared with load ratio of 2︰1, pH=2-3 and calcination temperature of 500 ℃ have the best photocatalytic performance and good thermal stability. When the dosage of TiO2/diatomite composite is 1 g/L, the degradation rate of 60 mL (10 mg/L) methyl orange solution within 60 min can reach 92%.