中文摘要：

传统的Langmuir—Hinshelwood方程式不能定性、定量地解释H-酸在TiO2表面的吸附平衡常数K与其在TiO2悬浮液中的光催化降解速率r之间的关系．这是因为在实际测定中，吸附平衡常数KL一般是通过给定有机物的平衡吸附量和平衡浓度而求得的．这样的KL不能表达给定有机物不同吸附模式吸附力的差别．因而以往的理论方法不能描述吸附力对光催化降解动力学的影响，而只能描述吸附量对r的影响．亚稳平衡态吸附（MEA）理论认为，同一吸附质在相同的热力学条件下可以不同的MEA态（包括同一溶质的不同吸附构型／模式）达到实际的吸附终态．从MEA的概念对Langmuir-Hinshelwood模型进行半经验性修正，可以较好地描述吸附量和吸附力（吸附模式）共同对H-酸在TiO2悬浮液中光催化降解动力学的影响．

英文摘要：

When Langmuir-Hinshelwood model is used to describe the photocatalytic degradation kinetics of H-acid on TiO2 surface, it is difficult to explain the experimental results on the relationship between the equilibrium adsorption constant and the degradation rate constant. This is because different adsorption modes of H-acid on the TiO2surface could not be described by the traditional adsorption thermodynamic theories. Metastable-equilibrium adsorption theory （MEA） theory was applied to modify Langmuir-Hinshelwood model. The modified MEA-Langmuir-Hinshelwood model can well explain qualitatively and quantitatively the photo-degradation ki- netics of H-acid under different pH conditions. It was concluded that adsorption modes and adsorption amount both affect the photo-degradation rates of H-acid, but the former played a dominant role.