Adsorptive removal of basic dye onto sustainable chitosan beads: Equilibrium, kinetics, stability, continuous-mode adsorption and mechanism

This study aims to develop sustainable low c chitosan-based beads by a simple dropping method, with instantaneous formation by re ula ion with trip yphosphate anion. The beads were characterized and applied to basic blue 7 uptake. Ads ption process was op mized through variation of several parameters in batch experiments such as beads lo ding, pH, dye con ntration and temperature. The best BB7 adsorption capacity by chitosan-beads was achiev in 60 min (117 mg/g), which was quite superior to others described in the literature. Kinetics data cou be better fitte to pseudo-first order and the adsorption process was better described by the La muir type del, MX bclass. The thermodynamic parameters calculated suggested that the adsorption process xothermic a avorable. The beads storage study indicated that for a two-week period their adsorption capacity w not affected. Also, the presence of interfering agents did not harmed basic blue 7 removal, especially in saline soln. In addition, in the continuous-mode it was achieved 100% of dye uptake in the initial 2h. Furthermore, the remval mechanism study suggests that hydrogen bounds are the main interaction bet n chitosan beads and the dye. This study gave rise to encouraging results and sustainable chitosan/tripolyphospha beads proved o be potential adsorbents for industrial effluent treatments, although in the presen of other yes and saline medium. This procedure allows wastewater to be reused for further ap catio