Abstract
The present research offers a comparative study on the character of the performance of dye removal using either functionalized silica or raw silica gel as adsorbents. First, these supports were characterized in terms of FT-IR and SEM analyses. Then, four different dye solutions were checked for the adsorption phenomenon: Eriochrome Black B (an acid dye), Methylene Blue (a basic dye), Direct Yellow 50 (a direct dye), and Reactive Blue 49 (a reactive dye). Experimental data revealed a dependence on the experimental conditions. Functionalized silica presented a higher removal of dyes than the raw silica. Among the four studied dyes, the highest capacity removal was achieved with Eriochrome Blue Black B (140 mg g
−1
) using functionalized silica as adsorbent. This value was reduced to 55 mg g
−1
for raw silica. Further, kinetic and thermodynamic investigations of Eriochrome were discussed. Results gleaned from this study suggest that the functionalized silica could be considered as an efficient candidate to treat colored waters.