The adsorption characteristics of nitrate on Mg–Fe and Mg–Al layered double hydroxides in a simulated soil solution

Anion Selectivity of Layered Double Hydroxides: Effects of Crystallinity and Charge Density

“…[ [21][22][23][24][25][26] In those previous studies, only a limited range of the M 2+ /M 3+ molar ratios was investigated, the effect of crystallinity or LDH size was only insufficiently examined, and the behavior of monovalent anions other than NO 3 -was not clarified. In addition, small LDHs, with crystallite dimensions of ca.…”

“…It is therefore very questionable whether LDHs could be used as nitrate adsorbents. However, several recent studies have reported that certain LDHs with specific compositions [21][22][23][24][25][26][27][28] show high selectivity for nitrate ions. Those reports, however, did not address the question of whether only the nitrate anion among monovalent anions and anions of low charge densities has a high affinity for LDHs under certain conditions.…”

Effect of Non-Thermal Plasma Modified NiAl Layered Double Hydroxides on the Removal of Fluoride from Aqueous Solution

“…This may be due to a high negative charge density of ions which were easily absorbed by the PO − ion appears to display a maximum interference for F − ion. Halajnia et al [32] showed that some physical properties of LDHs such as crystallinity, porosity, particle size, surface area and interlayer space characteristics can have great effects in adsorption.…”

“…The removal efficiencies were found to be 93.4%, 85.7%, 74.2% at the initial F − concentrations of 60.0, 80.0 and 100.0 mg/L, respectively. According to Halajnia and Oustan [32] the percentage removal at equilibrium depends on the type of LDHs as well as the initial concentration. On the other hand, seen from the removal time figure, with the increase of the initial F − concentrations from 60 to 100 mg/L, the total amount of F − adsorbed increased from 28.02 to 37.12 mg/g.…”

Simultaneous removal of Cl− and SO4 2− from seawater using Mg−Al oxide: kinetics and equilibrium studies

“…Their uptake of contaminants from aqueous solutions has been studied; these include reactive brilliant orange X-GN, arsenate, arsenite, fluoride, bromate, bromide, selenate, borate, nitrate, and chromate (Chubar 2011;Wu et al 2011;Lv et al 2012;Halajnia et al 2012;Yu et al 2012). As expressed in Eq.…”