Magnetic alginate beads with high basic dye removal potential and excellent regeneration ability

Abstract

The adsorption of crystal violet dye (CV) onto magnetic alginate composite (MAlg) from aqueous solutions was studied. Experiments were carried out as function of contact time, dosage, temperature, pH and CV concentration in the solutions. Optimum CV uptake was observed at equilibrium pH 7 and most of the CV was sorbed within 30 min. The equilibrium adsorption data were analyzed using two common adsorption models: Langmuir and Freundlich. The results revealed that Langmuir isotherm fit the experimental results well. The maximum adsorption capacity obtained from Langmuir isotherm equation was 0.113 mmol g−1 at 298±1 K. The kinetics adsorption of CV onto MAlg composite was investigated using the pseudo first order and pseudo second order kinetic models. The results showed that the adsorption of CV onto MAlg composite followed pseudo second order kinetic model. Thermodynamic data indicated that adsorption process is endothermic and spontaneous reaction. Due to their outstanding adsorption capacities, MAlg composite is an excellent adsorbent for the removal of CV. The Composite regeneration was greater than 98.6% with 0.01 M HCl, and MAlg composite could be repeatedly utilized for CV removal with negligible loss in sorption capacity.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author