The FTIR
spectra were obtained (KBr) using a Perkin Elmer Spectrum 100
Model Fourier Transform Infrared Spectrometer to observe the
surface functional groups. The elemental analyses were performed
to determine C/N ratio in natural- and DAH-bentonite
by using the Vario EL III Elemental Analyzer. Thermal analysis
(Setaram, Labsys TG-DTA Model) was carried out to observe
the modification is accomplished or not. The thermal analyses
for natural bentonite and DAH-bentonite were recorded in
the temperature range 25–1000 8C at a heating rate of
10 8Cmin