Resource utilization and photocatalytic performance of polytitanium salt dealgal sludge
Pt-loaded TiO2 photocatalytic catalyst(Pt@TiO2)was obtained via photodeposition of Pt on TiO2 nanoparticles,which were prepared from titanium-coagulated algae-rich sludge by one-step calcination method,and characterized by XRD,SEM,TEM,EDS and BET.The photocatalytic performance of Pt@TiO2 with different Pt loading amouts(based on the mass of TiO2 nanoparticles,the same below)on 4-chloropol(4-CP)degradation was analyzed through PL spectrum and UV-Vis DRS spectrum.The effects of Pt@TiO2 dosage(that is,the added mass of 4-CP solution in a certain volume,the same below),4-CP mass concentration,solution pH and humic acid mass concentration on the degradation rate of 4-CP were evaluated,followed by assessment on the cyclic stability of the optimal catalyst.The results indicated that 0.3%Pt@TiO2 with 0.3%Pt loading amount exhibited the best photocatalytic activity for the degradation of 4-CP,which had a nanospheroidal(mesoporous)structure with an average pore size of about 10 nm and lattice spacing of 0.350 nm.Under the conditions of 4-CP initial mass concentration 20 mg/L,0.3%Pt@TiO2 dosage 0.5 g/L and pH 7,4-CP could be completely degraded within 60 min.The active species of Pt@TiO2 photocatalytic degradation on 4-CP were hydroxyl radical and superoxide radical,and 92.5%of 4-CP could still be degraded by 0.3%Pt@TiO2 after 5 times of recycling.