Effect of temperature is another significant physico-chemical
process parameter because temperature will change the adsorption
capacity of the adsorbent [69]. If the amount of adsorption increases
with increasing temperature then the adsorption is an endothermic
process. This may be due to increasing mobility of the dye molecules
and an increase in the number of active sites for the adsorption with
increasing temperature. Whereas the decrease of adsorption capacity
with increasing temperature indicates that the adsorption is an exothermic
process. This may be due to increasing temperature decreasing the
adsorptive forces between the dye species and the active sites on the
adsorbent surface as a result of decreasing the amount of adsorption
[18]. Table 6 showed the compilation of results of various studies on
the effect of temperature on the dye adsorption by various adsorbents