Acid-Base Properties and Adsorption Behaviors of Heavy Metal Ions at the Surface of gamma-Al2O3/SiO2 Nano-Mixed System

作者：Huang Pei Pei; Sun He Yun; Fan Jia Ni; Sun Zhong Xi^*

来源：Acta Physico - Chimica Sinica, 2012, 28(6): 1425-1431.

DOI：10.3866/PKU.WHXB201203091

• gamma-Al2O3/SiO2 nano-mixed system
• Cu2+, Pb2+, Zn2+
• Acid-base
• Surface complexation
• Equilibrium constant

The surface acid-base properties of a gamma-Al2O3/SiO2 nano-mixed system were studied by potentiometric titration technique. Based on experimental data complemented by surface complexation theory of Constant Capacitance Model, the relevant equilibrium constants of surface acid-base reactions in the nano-mixed system were calculated using the WinSGW program as: XOH + H+ reversible arrow XOH2+ (lgK(1)=5.06 +/- 0.05); XOH reversible arrow XO-+H+ (lgK(2)=-8.45 +/- 0.10). Furthermore, the adsorption of heavy metal ions (Cu2+, Pb2+, Zn2+) at the surface of the gamma-Al2O3/SiO2 nano-mixed system was studied as a function of pH. Again using WinSGW software, the surface complexation constants of Cu2+, Pb2+ and Zn2+ ions in aqueous suspensions of gamma-Al2O3/SiO2 mixed systems were established respectively as: XOH+M2+reversible arrow XOM++H+ [lgK=-2.20, -1.72, -2.90 (M=Cu, Pb, Zn)]

• 出版日期2012-6
• 单位济南大学