The effect of surfactant on the charge behavior and coagulation of TiO2 nanoparticles suspension

Abstract

Abstract. In order to understanding of the fate and transport of TiO 2 nanoparticles (Nps) in the water treatment process, this study focus on the particle surface characteristics and coagulation process at different anionic surfactant sodium dodecylbenzene sulfonate (SDBS) and cationic surfactant cetyltrimethylammonium bromide (CTAB) concentration, using aluminum sulfate (AS) as a coagulant. Malvern Zetasizer nano-ZS measure the changes of zeta potential of TiO 2 Nps mixture and coagulation of flocs (Alu-TiO 2 ). Jar tests are conducted to evaluate the effect of surfactant on removal efficiency of TiO 2 NPs. Experimental results indicated that the adsorption of CTAB on TiO 2 Nps resulte in more positively charged surface. SDBS is more easily adsorbed on the surface of positively charged Alu-TiO 2 flocs. The presence of SDBS or CTAB have disadvantage of the removal of TiO 2 Nps during the coagulation process.