KINETICS OF LEAD(Ⅱ) DESORPTION ON THE SURFACE OF KAOLINITE
- 海洋环境－已发表论文 
经过酸性条件下 (p H=3.1) Pb( )高岭石表面解吸动力学的研究 ,发现解吸反应与吸附反应动力学相似 ,也是一个二阶段的过程 ,即初始的快速解吸之后伴随着一个缓慢的释放过程。在快速解吸阶段 ,7m in内解吸量即已达到 4 1%。吸附铅没有完全解吸 ,有近 38%残留在高岭石表面 ,即解吸和吸附过程不是完全可逆的。解吸过程可以用扩展Elovich方程、Elovich方程、双常数方程和一级扩散方程较好地拟合。The kinetics of Pb(Ⅱ) desorption on kaolinite was studied at the acidic condition(pH=3.1).The results showed that,similar to the adsorption kinetics, the desorption kinetics was biphasic, that is, an initially fast desorption followed by a slow release. During the fast stage, 41% of the sorbed Pb(Ⅱ) was desorbed from the surface within 7 min. The sorbed Pb(Ⅱ) didn't desorbed completely, with about 38% remaining on kaolinite. This suggested that the adsorption and desorption processes were not totally reversible. Furthermore, the desorption kinetics could be well fitted with extended Elovich, Elovich, two constant and first order diffusion equations.