Effect of calcination on adsorption performance of Mg–Al layered double hydroxide prepared by a water-in-oil microemulsion method

Abstract

Herein, Mg-Al layered double hydroxide (LDH) was firstly prepared by a water-in-oil microemulsion method and the prepared LDH sample was further calcined at different temperatures. The calcined LDH samples were carefully characterized using XRD, nitrogen adsorption, TEM, TGA, XPS, FTIR and zeta potential measurement. Calcined and uncalcined LDHs samples were used as adsorbents to remove orange II (O-II) dye in water. Adsorption experiments indicated calcination temperatures had an obvious 10 influence on the adsorption affinity of LDH, and the 500 º C calcined LDH sample (LDH-500) exhibiting the maximum adsorption capacity of 602 mg/g larger than that of LDH (224 mg/g). The pseudo-secondorder model was the best kinetic model to describe O-II adsorbed on the surface of the adsorbent, and the dye adsorption was well fitted using the Langmuir model for the prepared samples. The adsorption mechanism of O-II dye onto the calcined and uncalcined LDHs samples was mainly related to 15 electrostatic interaction between the anionic O-II molecules and positively charged surface of the adsorbents, and the slow intercalation of O-II into the layers of LDH and reconstruction of LDH-500.

Rational Design of a Coupled Confronting Z‐Scheme System Toward Photocatalytic Refractory Pollutant Degradation and Water Splitting Reaction

“…Figure b,c represents similar type of behavior for V and O in BCL. The O 1s symmetric spectra consist of three distinct deconvoluted peaks at 530.9 (I′), 532.2 (II′), and 533 eV (III′) ascribed to lattice oxygen of L and layered Bi 2 O 2 2+ of B, oxygen in OH − /CO 3 2− , and chemisorbed H 2 O, respectively . The decrease in electron availability in the conduction band of B in BCL and formation of the SBiO chemical bond between C and B are confirmed from this.…”

Reverse Microemulsion‐Assisted Synthesis of NiCo2S4 Nanoflakes Supported on Nickel Foam for Electrochemical Overall Water Splitting

“…Here, cetyltrimethyl ammonium bromide (CTAB) and n ‐butyl alcohol were used as surfactant for adjusting the size distribution of micelles. N ‐butyl alcohol can be preferably adsorbed on the crystal plane of Ni–Co intermediates via hydrogen bonding with the OH groups present on its surface . Generally, the adsorption of n ‐butyl alcohol molecules will inevitably rely on the surface density of NiCo atoms, and the adsorption of surfactants block the surface with high surface density of atoms to grow crystal of nanocrystals.…”

A Polyoxoniobate/g-C3N4 Nanoporous Material with High Adsorption Capacity of Methylene Blue from Aqueous Solution

“…In order to eliminate organic dyes from waste water, several methods including adsorption (Haque et al, 2011 ; Wang et al, 2016 ; Yan et al, 2016 ), photo-degradation (Kumar et al, 2014 ; He et al, 2015 ; Xin et al, 2017 ), chemical oxidation (Osugi et al, 2009 ), and biological treatment (Zhang et al, 2014 ) have been used. Compared to others, adsorption is considered as a most effective method due to its simple design and operation, high efficiency, and economy (Haque et al, 2011 ).…”