Abstract:In order to investigate the feasibility of removing the nanoparticles(NPs) from water by coagulation, the effects of inorganic coagulants (PAC, PFS, PAFC) and organic flocculants (CPAM, APAM, NPAM) on the removal efficiency of TiO2 NPs were evaluated. The effects of dosage, pH, sedimentation time, hydraulic conditions and compound flocculants were also investigated. The highest removal rates of PAC, PFS and PAFC were 92.51%, 84.43% and 95.66% while the removal rates of CPAM, APAM and NPAM were only 61.72%, 29.06% and 55.37% respectively. The optimum coagulation dosage were 40 mg/L PAC and 3 mg/L CPAM, while the pH was 9, G value was 143.5/s and the sedimentation time was 15min,and the corresponding removal efficiency of TiO2 NPs was 99.6%.