Enhanced extraction of methylene blue by dodecyl-methyl imidazolium dodecyl sulfate GUMBOS - magnetic alginate beads

Abstract

In this study, dodecyl-methyl imidazolium dodecyl sulfonate ([C₁₂MIm][DS]) GUMBOS were synthesized and incorporated into alginate with γ-Fe₂O₃ to fabricate magnetic adsorbent beads ([C₁₂MIm][DS]-beads) for methylene blue (MB) removal. Characterization via ESI-MS, FT-IR, SEM, BET, and TGA confirmed their structure and properties. The beads achieved a maximum adsorption capacity of 4.5 mg/g at pH 10 with an initial MB concentration of 500 mg/L, following pseudo-first-order kinetics and the Langmuir isotherm model. Thermodynamic studies confirmed the process was exothermic. Even after six recycling cycles, the beads retained similar morphology and an MB removal percentage of 57.6%. The beads demonstrated high adsorption efficiency (70%) in the presence of Cu²⁺, ibuprofen, and malachite green, comparable to MB removal alone. These results highlight the potential of [C₁₂MIm][DS]-beads as effective adsorbents for water remediation applications.