Sorption of As(V) from aqueous solution using in situ growth MgAl–NO3 layered double hydroxide thin film developed on AA6082

Abstract

In this work, the MgAl-NO 3 layered double hydroxide (LDH) developed by the single-step in situ growth method is used as a robust sorbent to remove arsenic from aqueous solution. The MgAl-LDH exhibiting two different distinct morphologies (platelet structure and cauliflower-shaped structure) was developed on the AA6082 substrate with the variation in synthesis parameters, where AA6082 specimen acts as both the reactant and support. The structural characterizations were investigated through scanning electron microscopy, X-ray diffraction analysis, and energy dispersion spectroscopy, while the adsorption of arsenic on MgAl-LDH was studied through Langmuir and Freundlich models. The Langmuir isotherms have shown a maximum adsorption capacity of around 213 and 239 mg/g for platelet and cauliflower-like MgAl-LDH, respectively. The pseudo-first-order and pseudo-second-order Lagergren kinetic models were studied for the understanding of the adsorption kinetics. The results depicted that anion exchange and the electrostatic interaction are the possible reasons of arsenic sorption on MgAl-LDH, but the ion exchange mechanism is found to be the dominant mechanism. The maximum adsorption capacity of cauliflower-shaped MgAl-LDH was found to be slightly higher than platelet structure, but overall maximum arsenic adsorption uptake values of both in situ growth structures have found to be exceeded the mostly reported MgAl-LDH maximum adsorption capacities.

Ce-Doped-MgAl Superhydrophobic Layered Double Hydroxide for Enhanced Corrosion Resistance Properties

“…However, aggressive solutions are found to disrupt the protective aluminum oxide layer, which causes an initiation of the corrosion reaction and limits their usage in the application ranges [1]. Layered double hydroxides (LDHs) have received considerable attention due to their unique characteristics, like ion-exchange properties, tunable interior architecture, porosity, interlayer distance, and flexible composition range, which make them suitable in numerous fields like catalyst [2], fertilization [3], environmental science [4], adsorption [5], and energy systems [6].…”

Layered Double Hydroxide Protective Films Developed on Aluminum and Aluminum Alloys: Synthetic Methods and Anti-Corrosion Mechanisms

“…Due to the anion exchange capability of LDHs, various anions can be successfully incorporated inside the LDH interlayer to modify the chemistry of LDH for specific applications: for instance, supercapacitors, environmental sciences, catalysts, adsorption, etc. [31][32][33][34][35][36][37]. Recently, regarding the subject of anti-corrosion materials, layered double hydroxide (LDH)-based coating systems have also been widely explored, due to LDHs' peculiar morphology, a wide range of cationic/anions combinations, environmental friendliness, barrier properties, high surface to volume ratio and multifunctional design along with the capability to intercalate various species, such as metal ions of mixed valences, complex inorganic, organic molecules in the in LDH interlayers, and thus can be utilized as multifunctional coating systems.…”

Chlorides Entrapment Capability of Various In-Situ Grown NiAl-LDHs: Structural and Corrosion Resistance Properties

“…In that scenario, numerous approaches have been studied to develop economic coating systems to protect aluminum alloys, for instance, magnetron sputtering [1], anodizing [2], self-assemble [3], polymeric coatings [4], and chemical conversion techniques [5]. Recently, layered double hydroxides (LDHs) have got prominent attention for potential applications in various fields, including, adsorbents [6], drug delivery systems [7], environmental sciences [8], and biomedical science [9]. LDHs have also be found an efficient system to enhance corrosion resistance due to their ion-exchange capabilities, high surface area, a wide range of cationic salts availability, cost-effectiveness and other lucrative characteristics [10][11][12].…”