Abstract
Acid-activation of bentonite was optimised to prepare an effective adsorbent of toluene. The activated bentonite was obtained with a specific surface area of 195
m
2/g, a pore volume of about 0.46
cm
3/g and a most frequent pore size of 62
Å. Compared to the raw bentonite, the adsorption of toluene onto acid-activated bentonite was increased from 66
mg/g to 197
mg/g. Vapor–solid adsorption isotherms of toluene were measured at 120
°C, 140
°C, 160
°C and 182
°C using an inverse gas chromatography. The experimental data were correlated with different adsorption isotherm models such as Langmuir, Freundlich, Langmuir–Freundlich and Toth models. Only the Langmuir–Freundlich equation provided good fit to the experimental data.