Valorisation of rhodamine B adsorbed copolymer beads for the recovery of Cu2+ from e-waste: Green approach

The methacrylic acid-divinylbenzene copolymer beads were prepared by suspension polymerization and used for the removal of rhodamine B (RhB) dye. Batch experiments were carried out to find the adsorption parameters. Langmuir adsorption isotherm model was found to be the best suited for the adsorption of RhB on the copolymer beads. The RhB adsorbed copolymer beads were valorised as adsorbent for the removal of Cu2+ from e-waste solution, which was compared with electrolytic solution. The Cu2+ loaded on the RhB containing copolymer beads was recovered by using 1 M HNO3 The RhB loaded on the copolymer beads were successfully eluted by using a mixture of acetone and acetic acid. Selectivity of RhB dye for the recovery of Cu2+ ions from e-waste was also carried out in this work. Methods were developed to recover both the Cu2+ and RhB dye separately. Microscopic analysis was performed to understand the adsorption of RhB and ion-exchange of Cu2+ onto the copolymer beads.