粘土基陶粒的制备及其对Cd^(2+)的吸附性能研究

Preparation of Ceramsite Based on Clay and Its Static Adsorption Study for Cd^(2+)

以粘土为骨料,采用添加造孔剂法制备了多孔陶粒,将其作为吸附材料,研究了陶粒对Cd^(2+)的吸附能力、吸附动力学和吸附机理。结果表明,粘土基多孔陶粒对Cd^(2+)具有良好的吸附能力。固液比较大时,得到的吸附量值较小,且随着固液比的增大,陶粒对Cd^(2+)的吸附效率和吸附速率均下降。吸附动力学模型研究表明,陶粒对Cd^(2+)的吸附符合准二级吸附速率方程,颗粒内扩散模型确定吸附过程由2个或多个步骤控制。陶粒中的-OH、C-O基团参与对Cd^(2+)的吸附,形成了CdO新相,说明陶粒对Cd^(2+)的吸附包括化学吸附。

The adsorption capacity of porous ceramsite based on clay is prepared by pore-forming method as adsorption material. The ceramsite on Cd2＋ , the adsorption kinetics and mechanism are investigated. The results show that the ceramsite based on clay has an excellent Cd2＋ adsorption capacity. When the s/w is relativehy high, the adsorption quantity is relatively small. The adsorption efficiency and rate of ceramsite on Cd2＋ decrease with the increase of s/w. The adsorption process divides into the outside surface adsorption and the balanced adsorption stages, the first stage carries on quickly, achieving in 30min. The adsorption kinetics models show that, Quasi-two adsorption rate equation fits well with the Cd2＋ adsorption of ceramsite. Intrapartical transport model proves that the adsorption process is controlled By two or more procedures. The -OH and （2-0 groups of the ceramsite participates in the Cd2＋ adsorption and kainotype CdO is formed, showing that the Cd2＋ adsorption of ceramsite is chemical adsorption.