A novel bead synthesis of the Chiron-sodium dodecyl sulfate hydrogel and its kinetics-thermodynamics study of superb adsorption of alizarin red S from aqueous solution

Abstract

We present a novel strategy for one step synthesis of iron (III) hydroxide doped chitosan (“Chiron”) without using acidic solvent via sodium dodecyl sulfate (SDS) as surfactant gelation, namely, Chiron-SDS hydrogel bead. The Chiron-SDS is developed as a potentially attractive adsorbent for an investigation of the noxious anionic dye from aqueous solution. The bead formation was obtained from 20 μL of the Chiron solution, and their uniform bead diameter was observed about 179 ± 0.13 μm, of which containing 86.7% moisture or 6 × 10−5 g DW per bead. Alizarin red S (AR) was chosen as pollutant model and was monitored spectrophometrically at 425 nm. The bead size after AR adsorption was slightly larger (185 ± 0.10 μm) than that of its original one. Fourier transform infrared analysis indicated that the Fe (OH)3 were chelated with chitosan structure in the Chiron-SDS beads. The equilibrium data fit to Langmuir as the best representative model (R2 0.99), and their kinetics data are well fitted with the pseudo-second order. It was found that the maximum adsorption capacity (qm) from Langmuir model for AR by Chiron-SDS is 294 mg g−1, which was much higher than those previously reported data. The calculated thermodynamic parameters show that the dye adsorption is spontaneous and endothermic process. The advantage characteristics of ease, low cost, eco-friendly, and superb high adsorption efficiency demonstrate that this output gives a great deal to step forward for a huge scale elimination of toxic dye contaminants from aqueous solution, leading usefulness further for an environmental remediation. © 2019, The Polymer Society, Taipei.