MATERIALS AND METHODS
Materials: Bentonite clay from Jeddah city, Saudi Arabia was used as an adsorbent. The
chromium (Cr) and lead (Pb) ions solution were prepared from chromium nitrate and lead nitrate
purified LR supplied by S. define-chem. Limited (Laboratory Rasayan) and used as adsorbate.
Characterization of Bentonite clay (adsorbent): Bentonite clay was analyzed chemically by
XRF (Table 1). The physical properties of Bentonite clay were determined by the standard methods
(Table 2). The XRD analysis of Bentonite clay verified that it contained 80% montmorillonite, 10%
kaolinite and illite and quartz as 10%.