School of Environmental Science and Engineering, Donghua University, Shanghai, PR China.
J Hazard Mater. 2011 Feb 15;186(1):765-72. doi: 10.1016/j.jhazmat.2010.11.063. Epub 2010 Nov 23.
A photocatalyst comprising nano-sized TiO(2) particles on granular activated carbon (GAC) was prepared by a sol-dipping-gel process. The TiO(2)/GAC composite was characterized by scanning electron microscopy (SEM), X-ray diffractiometry (XRD) and nitrogen sorptometry, and its photocatalytic activity was studied through the degradation of humic acid (HA) in a quartz glass reactor. The factors influencing photocatalysis were investigated and the GAC was found to be an ideal substrate for nano-sized TiO(2) immobilization. A 99.5% removal efficiency for HA from solution was achieved at an initial concentration of 15 mg/L in a period of 3h. It was found that degradation of HA on the TiO(2)/GAC composite was facilitated by the synergistic relationship between surface adsorption characteristics and photocatalytic potential. The fitting of experimental results with the Langmuir-Hinshelwood (L-H) model showed that the reaction rate constant and the adsorption constant values were 0.1124 mg/(L min) and 0.3402 L/mg. The latter is 1.7 times of the calculated value by fitting the adsorption equilibrium data into the Langmuir equation.
一种负载在颗粒状活性炭（GAC）上的纳米 TiO(2)光催化剂是通过溶胶-浸渍-凝胶法制备的。采用扫描电子显微镜（SEM）、X 射线衍射（XRD）和氮吸附法对 TiO(2)/GAC 复合材料进行了表征，并通过在石英玻璃反应器中降解腐殖酸（HA）研究了其光催化活性。考察了影响光催化的因素，发现 GAC 是纳米 TiO(2)固定化的理想载体。在初始浓度为 15mg/L 的条件下，经过 3h 的反应，溶液中 HA 的去除率达到 99.5%。研究发现，TiO(2)/GAC 复合材料上 HA 的降解是由表面吸附特性和光催化潜力之间的协同关系促进的。实验结果与 Langmuir-Hinshelwood（L-H）模型拟合表明，反应速率常数和吸附常数的值分别为 0.1124mg/（L min）和 0.3402L/mg。后者是通过将吸附平衡数据拟合到 Langmuir 方程得到的计算值的 1.7 倍。
