Sorption of methyl orange dye by dodecyl-sulfate intercalated Mg-Al layered double hydroxides

Abstract

The aim of this study is to evaluate the Mg-Al layered double hydroxides (LDHs) containing dodecyl sulfate and carbonate ions in the removal of methyl orange (MO) from aqueous solution. The prepared materials (Mg-Al-CO3 and Mg-Al-Ds) were characterized by XRD, TEM and FT-IR methods. XRD patterns of the two materialsshow the interlayer type structure with (00 l) reflections. TEM analysis showed that the LDH samples have nanoscale structures. FTIR spectroscopy confirmed the presence of the desired anions in the interlayer space. The results of the adsorption experiences for MO were performed as a function of solution pH and contact time. The adsorption ability of MO onto Mg-Al-CO3was practically influenced by pH solution. However, the adsorption capacity of MO by Mg-Al-Ds appears stable at the different values of solution pH. The maximum adsorption capacities were 185.06 and 97.5 mg/g for Mg-Al-Ds MB and Mg-Al-CO3, respectively. The adsorption tests recommend the use of organic LDHs as potential adsorbents for azo dye treatment in a wide range of pH.