Cationic Dye Removal Using Alginate–Organobentonite Composite Beads

In the present work, natural bentonite (B) was modified using hexadecyltrimethylammonium bromide (HDTMAB), as a modifying agent. The organobentonite material obtained (OB) was encapsulated in calcium alginate bead (A–OB) under three proportions (1/1, 2/1, and 3/1 w/w, respectively). The obtained materials were tested on the adsorption of methylene blue. The equilibrium data were also well adjusted to the Langmuir isothermal model in the studied concentration range of MB at room temperature. The obtained results indicate that the calcium alginate–organobentonite composite under 1/1 mixing ratio (w/w) was the most effective adsorbent for the adsorption of the methylene blue dye and the maximum amount of MB per gram of adsorbent (q_max) increases from 344.4 to 972.29 mg/g.