Co and Ni Double Substituted Zn-Fe Layered Double Hydroxide as 2D Nano-Adsorbent for Wastewater Treatment

Abstract

Recently, several types of nanomaterials gained attention as promising nanoadsorbents to remove dyes from wastewater such as layered double hydroxides (LDHs). In this work, Fe-Zn-Co-Ni LDH was developed by the basic co-precipitation method. In order to emphasize and characterize the developing of this quaternary LDH, six techniques (x-ray diffraction (XRD), scan electron microscope (SEM), Fourier transforms infrared (FTIR), transmission electron microscope (TEM), zeta potential measurements) have been investigated. The LDH was studied for the uptake of anionic dye, methyl orange (MO), under numerous adsorption factors such as solution pH, contact time, dye initial concentration and adsorbent dosage, and. The XRD data states that the crystallite size of MO@LDH (93.1 nm) is increased compared with that of LDH (12.7 nm) owning to the adsorption of MO onto LDH surface. Two new peaks have appeared for the MO@LDH owning to the bending vibrations of the MO functional groups C-N and C-H. The highest adsorption capacity for the prepared MO@LDH was 418 mg/g and it reached the equilibrium state at 60 min. The adsorption kinetic was obeyed to the pseudo-first order model. Additionally, the LDH showed a positive antibacterial effect towards both Gram-negative and Gram-positive bacteria.