Removal of anionic and cationic dyes from aqueous solution with activated organo-bentonite/sodium alginate encapsulated beads

Abstract

In this study, cross-linked activated organo-bentonite (AOBent)/sodium alginate (SA) composite was prepared by the intercalation of sodium alginate in activated organo-bentonite and the cross-linking reaction between sodium alginate and chlorhydric acid to produce interesting new low cost material for the removal of cationic and anionic dyes (methylene blue (MB) and methyl orange (MO)) from aqueous solutions. Adsorbents were characterized by using X-ray diffraction (XRD), thermal gravimetric analyses (TGA) and Fourier transform infrared spectroscopy (FTIR). Batch adsorption studies were carried out to evaluate the effect of pH solution, the kinetic and the isotherm on the adsorption capacity of the adsorbents. The kinetic of MB and MO adsorption was found to follow a pseudo-second-order kinetic model meanwhile the isotherm was well described by the Langmuir model for all samples. Results obtained from this study suggest the potential of prepared composites for cationic and anionic dyes removal which can also be used easily for clean and ecofriendly processes.