Abstract: (7590 Views)
The behauiours of clay minerals and the extent of clay-heavy metals interactions are
functions of CEC and the exposed SSA of the clay minerals. The type and the
quantity of double layer cations have an essential impact on this process. This work
aimed to investigate the behaviour of Na-montmorillonite and Ca-montmorillonite in
interaction with Pb as a heavy metal ion. The results showed that although the
buffering capacity pattern of montmorillonite and different concentrations of NaCl is
relatively similar, the contaminant retention property of montmorillonite is a function
of the quantity of sodium ions with which the soil is treated. In Ca-montmorillonite,
in spite of very small change in its buffering capacity in comparison with that of
montmorillonite, a noticeable change in contaminant retention was observed. This
emphasizes the limitation of buffering capacity experiment to determine the extent of
soil-contaminant interaction. On the other hand, retention experiment was able to
differentiate between the behaviour of these two samples. Finally, the results of the
interaction process of sodium- and calcium- montmorillonite with heavy metal
contaminant were compared using the XRD experiments.
Received: 2008/12/4 | Accepted: 2009/05/4 | Published: 2011/03/5