煤系高岭土合成Al-MCM-41及镧改性后有效脱除磷

Al-MCM-41 Materials Synthetized by Kaolin for Efficient Removal of Phosphate after Modifying by Lanthanum

用煤系高岭土作为硅源和铝源合成介孔分子筛Al-MCM-41,然后浸渍镧获得一种具有高吸附容量和磷去除率的新型磷酸根吸附剂。分别考察了载体和镧负载量对吸附磷酸根性能影响。硅铝比为48的介孔分子筛Al48-MCM-41具有非常规整的一维孔道结构,作为载体为负载镧氧化物提供一个好的空间结构。负载量为15%的La15-Al48-MCM-41磷酸根吸附量吸附时间先呈线性增长,后缓慢增加,最后趋于平衡,饱和吸附量为60.43 mg/g,投加量为0.12 g时磷去除率96.01%。通过比较不同初始pH值条件下吸附过程中的pH值变化情况,发现吸附剂表面上的羟基和磷酸根之间的离子交换是去除磷酸盐的主要原因。

The novel phosphate adsorbents were prepared through impregnating lanthanum onto the synthesized Al-MCM-41 by using coal-Kaolin as the whole silica and aluminum sources,to obtain a high adsorption capacity and P removal rate. In this paper,effects of different carriers and loading quantities on the phosphate adsorption capacity were investigated. The morphology Al48-MCM-41 has a very regular and one-dimensional pore channel providing a better space as the host for loading lanthanum oxides. The phosphorus adsorption of La15-Al48-M41 linearly increases with adsorption time,then increase slowly,finally the phosphorus adsorption tends to saturation and the adsorption quantity is 60. 43 mg /g. When dosing quantity is 0. 12 g,phosphorus removal rate is 96. 01%. By comparing the pH value varieties of different initial pH value,we concluded that the functional ion exchange between —OH on the surface of adsorbents and phosphate existed was the main reason for phosphate removal.