γ-Al_2O_3/SiO_2纳米颗粒混合体系表面的酸碱性质及其对重金属离子的吸附行为  

Acid-Base Properties and Adsorption Behaviors of Heavy Metal Ions at the Surface of γ-Al_2O_3/SiO_2 Nano-Mixed System

作　　者：黄佩佩[1] 孙和云[1] 樊佳妮[1] 孙中溪[1] 

机构地区：[1]济南大学化学化工学院,济南250022

出　　处：《物理化学学报》2012年第6期1425-1431,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(50874052;20677022);国家重大科学研究计划(2011CB933700)资助项目~~

摘　　要：运用电位滴定技术研究了γ-Al2O3/SiO2纳米颗粒混合体系的表面酸碱性质;依据滴定数据及表面配位理论恒电容模式,利用WinSGW软件计算得出了γ-Al2O3/SiO2纳米颗粒混合体系表面的酸碱反应平衡常数:≡XOH+H+≡XOH2+(lgK1=5.06±0.05);≡XOH≡XO-+H+(lgK2=-8.45±0.10);在此基础上研究了不同pH条件下重金属离子Cu2+,Pb2+,Zn2+在γ-Al2O3/SiO2纳米颗粒混合体系表面的吸附行为,并用WinSGW软件模拟得出了Cu2+,Pb2+,Zn2+在该混合悬浮液体系中的表面配位常数:≡XOH+M2+≡XOM++H+[lgK=-2.20,-1.72,-2.90(M=Cu,Pb,Zn)].The surface acid-base properties of a γ-Al2O3 /SiO 2 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 ＋ ≡XOH ＋ 2（lgK 1 =5.06± 0.05）;≡XOH ≡XO ＋H ＋（lgK 2 =-8.45±0.10）.Furthermore,the adsorption of heavy metal ions（Cu2＋,Pb2＋,Zn2＋） at the surface of the γ-Al2O3 /SiO 2 nano-mixed system was studied as a function of pH.Again using WinSGW software,the surface complexation constants of Cu 2＋,Pb 2＋ and Zn 2＋ ions in aqueous suspensions of γ-Al2O3 /SiO 2 mixed systems were established respectively as：≡XOH＋M 2＋ ≡XOM ＋ ＋H ＋ [lgK=-2.20,-1.72,-2.90（M=Cu,Pb,Zn）]

关 键 词：γ-Al2O3/SiO2纳米颗粒混合体系 Cu2+ Pb2+ Zn2+ 酸碱 表面配位 平衡常数 

分 类 号：O647.3[理学—物理化学] X131.3[理学—化学]