Studies on Adsorption of Surfactants on Activated Carbons. III.

Adsorption of Cationic Surfactant

Abstract

The adsorptivities of octadecyltrimethylammonium chloride (OTAC) on various activated carbons from aqueous solutions were investigated and the following results were obtained.
1) The obtained adsorption isotherms apparently were of the Langmuir type.
2) The occupied area (Sm) and Langmuir's constant (a) decreased with increasing the mean pore size of activated carbon.
3) The amounts of adsorption increased with increasing pH of the solution.
4) With the decrease in activation temperature of activated carbon, the effect of pH on adsorption of OTAC on the activated carbon increased.
5) The effect of the anion of coexisting electrolyte on adsorption was much larger than that of the cation, and this order followed the lyotropic series.