Résumé:
Cr(III)-intercalated montmorillonite was utilized as an adsorbent for the removal of the organic pollutant, Supranol Yellow 4GL, a synthetic
dye used for chemical fibres. The material was prepared by the reaction of Na montmorillonite with a base-hydrolyzed solution of Cr nitrate
salt (OH
−
/Cr
3+
molar ratios of 2). XRD data showed that the interlayer spacing (
d
001
) of montmorillonite was increased from 12.35 to 23.06
̊
A.
The kinetics and mechanism of the adsorption of the acid dye, Supranol Yellow 4GL, on Cr(III)-intercalated montmorillonite was investigated.
The equilibrium time was reached within 30 min. The process follows pseudo-second-order rate kinetics. The Langmuir isotherm described the
adsorption data over the concentration range (20–160 mg/l). The separator factor
R
L
revealed the favourable nature of this adsorption process. Also,
the thermodynamic parameters such as
S
◦
,
H
◦
,
G
◦
were determined.
© 2005 Elsevier B.V. All rights reserved.
