中文摘要：

以硅藻土原土为原料，通过碱洗及浸渍负载羟基氧化铁对其进行改性，利用SEM、XRD及物理吸附仪对改性硅藻土的形貌、比表面积等进行表征，并研究了改性硅藻土对富营养化水体中磷的吸附性能。结果表明，（1）改性后，硅藻土杂质元素减少，孔径明显增大，比表面积增大23倍，并有效负载了β-FeO（OH）；（2）其对磷的吸附受温度及pH值的影响，温度越高，达到吸附平衡时间越短，吸附容量也越大；在pH值为4～11之间，吸附容量随pH的增大而减小；（3）拟二级反应动力学方程，能准确地描述改性硅藻土对磷的吸附，而粒内扩散，不是改性硅藻土对磷吸附的唯一控制步骤；（4）改性硅藻土在富营养化水体中对磷的吸附行为，符合Freundlich等温线方程，其吸附过程为物理吸附，吸附过程焓变（△H）为39．949kJ／mol，各温度下的自由能变（AG）均小于零，熵变（△S）均为正值，该吸附过程是自发的吸热物理过程。

英文摘要：

In this study, diatomite was modified by alkali-cleaning and loaded technics, examined by SEM, XRD and physical adsorption, and phosphorus-sorption experiment was researched in eutrophication water. The results were shown as fellow： （1） After modified, the content of impurity element decreased, bore diameter of modified diatomite increased obviously, the surface area of modified diatomite had increased 23 times, and β-FeO（OH） was loaded on the surface effectively; （2） Phosphorus sorption was affected by the temperature and pH value, if temperature was higher, the sorption balance time was shorter; adsorption capacity was decreased when pH value was increased from 4 to 11; （3） Pseudo-second reaction kinetics equation could describe characteristics of phosphorus sorption well, intragranular diffusion wasn＇t only control step of phosphorus sorption; （4） Phosphorus sorption behavior of modified diatomite could be simulated by Freundlich adsorption isotherm model, the sorption process was physical adsorption, the enthalpy changes of the adsorption process was 39.949kJ/mol. At various temperatures, △G was negative and △S was positive, which indicated adsorption of phosphorus by modified diatomite was endothermic and spontaneous physical process.