The optimum pH for adsorption was
found to be 6.0. Residual cadmium concentration reached equilibrium in 6 h and the rate
of cadmium adsorption by perlite was rapid in the first hour of the reaction time. Ho’s pseudo-second order
model best described the kinetics of the reaction. Batch adsorption experiments conducted at
room temperature (22±1 ◦C) showed that the adsorption pattern followed the Freundlich isotherm
model. The maximum removal of cadmium obtained from batch studies was 55%. Thomas model
was used to describe the adsorption data from column studies. The results generally showed that
perlite could be considered as a potential adsorbent for cadmium removal from aqueous solutions.
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