For the manufacture of modified activated carbon,
the activated carbon was washed with distilled
water and was dried in an oven at 100 °C
for 24 h. The washed carbon was then divided in
2.5 g portions and a 50 ml of TBA containing
solutions were added. The initial concentrations
of TBA were varied from 60 to 1000 mg l−1
. The
2.5 g activated portions were remained in agitating
contact with TBA solutions and after 3 days,
the aqueous solutions were sampled and the concentrations
determined. When samples showed no
concentration difference, the system was considered
to be in equilibrium. The amount of TBA
adsorbed was calculated by making a masse balance.
The TBA concentration was analysed by
measuring its absorbance at 228 nm (DR 5000
UV–vis spectrophotometer). The molar extinction
coefficient m of the calibration curve was 1.0×
104 l mol−1 cm−1 in the range 5–25 mg l−1
.
Details of SDDC adsorption procedure have previously
been described [13].