high efficient dye removal by recyclable magnetite core-shell adsorbent

An environmental-friendly magnetic adsorbent composed of chitosan, graphene oxide and diethylenetriaminepentaacetic acid (dtpa) was synthesized and used to remove methyl violet cationic dye from aqueous solution as a wastewater model. the sorbent was characterized by ftir, fesem, xrd, eds, tga and vsm. the adsorption conditions were optimized by pre-experiment and the removal percentage of 95.7% was obtained for 10 mg/l of dye at ph = 9.8, temperature of 52.3 °c and adsorbent dosage of 0.01 g. based on the kinetic study, the adsorption process was too fast and the modified pseudo-n-order was the best model to fit the experimental data. besides, the maximum adsorption capacity of 243.8 mg/g was obtained by equilibrium experiments correlated successfully by the langmuir-freundlich isotherm. the reusability of magnetite core-shell sorbent was tested showing no significant decreasing in the dye removing capability of adsorbent.