Removal of Gallic Acid Over Layered Double Hydroxide: Material Design and Kinetic Studies

Abstract

The present study focused on removing gallic acid on the layered double hydroxide (Mg-Al-LDH) material synthesized by the co-precipitation method with a molar ratio of Mg/Al = 2. The elaborated Mg-Al-LDH was characterized using chemical analysis, XRD, FTIR, SEM, and specific surface area techniques. Langmuir and Freundlich isotherms and kinetic studies were also investigated. The adsorption tests demonstrated that the GA adsorption onto the Mg-Al-LDH is dependent on the material dose, GA concentration, and the pH of the solution. It was observed that the yield of the dye removal passed from 27.37 to 99.9 %; when the Mg-Al-HDL dose increased from 0.05 to 0.8 g/L. The results obtained showed that the adsorption of GA on Mg-Al-LDH is an endothermic reaction, spontaneous, follows second-order kinetics, and the Langmuir isotherm observed a better description.