Synergistic effect of humic and fulvic acids on Ni removal by the calcined Mg/Al layered double hydroxide

Abstract

Discharge of Ni(II) containing wastewater to terrestrial environment can lead to serious pollution issues. This study presents a facile, cost-effective and highly efficient method to rapidly remove Ni(II) from wastewater using a calcined Mg/Al layered double hydroxide (LDH), which is a pioneering investigation of using the calcined LDH to remove the positively charged Ni(II) ions. The kinetic studies showed that the removal of Ni(II) was very rapid with a pseudo first order k of up to 3.6 AE 0.5 h À1 , and maximum removal of Ni(II) was up to 204.2 AE 10.6 mg g À1 . In addition, our results reveal that both humic (HA) and fulvic acids (FA) can strongly bind to the surface of the LDH, which demonstrates that the calcined LDH can effectively remove both cationic and anionic pollutants in a single process. With the increase of pH up to 7.5, the removal of Ni, HA and FA by the calcined LDH are all drastically enhanced. Our study also demonstrated a strong synergetic effect of FA and HA on the Ni(II) removal by the calcined LDH, with a maximum Ni(II) removal of 290.6 AE 16.4 mg g À1 and 480.4 AE 21.3 mg g À1 at pH 7, respectively. The possible mechanism of the Ni(II) removal can be due to the incorporation of Ni into the layered structure by replacing the

Carbohydrate-based activated carbon with high surface acidity and basicity for nickel removal from synthetic wastewater

“…7,8 Hence, nickel compounds have been considered as a priority pollutant by institutions around the world (e.g. EPA U.S. 9 and WHO/IARC 10 ). Moreover, there is an increasing demand for developing more effective techniques to remove such pollutant from wastewater.…”

Physicochemical Properties and Hematocompatibility of Layered Double Hydroxide-Based Anticancer Drug Methotrexate Delivery System

“…As indicated in the open circle curve in Figure 3 A, the average zeta potential of MTX-LDH at neutral pH was 4.61 ± 0.97 mV, showing almost neutral surface charge. Generally, the zeta potential of LDH at neutral pH is very positive, ~+30 mV [ 3 , 55 , 56 , 57 , 58 ], due to the strong positive charge density of LDH layers. However, the zeta potential drops to the neutral value region due to the MTX moieties, which were mostly intercalated into LDH but partially covered the outer surface of LDH layers [ 44 ].…”

Rapid removal of Ni(II) from aqueous solution using 3-Mercaptopropionic acid functionalized bio magnetite nanoparticles

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