LAUSR

In this paper, we prepared monodisperse porous silica nanospheres (SiO2 NSs) to adsorb organic dyes. The obtained porous SiO2 NSs have uniform size of ~ 350 nm in diameter. Zeta potential result reveals the obtained porous SiO2 NSs are negative charged. The adsorption property of porous SiO2 NSs was analyzed by various influenced factors, such as adsorbent doses, adsorption time, removal efficiency, and adsorption capacity and recycle adsorption capability. In a very short adsorption time of 5 min, the obtained porous SiO2 NSs have efficient removal efficiency of 99.71% (for Alcian blue) and 99.06% (for methylene blue) and high adsorption capacity of 250 mg/g (for Alcian blue) and 160 mg/g (for methylene blue), higher than previously reported adsorbents. Recycle adsorption experiments (using calcination method) show that porous SiO2 NSs could be recycled at least six times while the removal efficiency had no significant decrease (< 2%).