Preparation of Molybdenum Disulfide Coated Mg/Al Layered Double Hydroxide Composites for Efficient Removal of Chromium(VI)

Abstract

With the rapid development of industry, heavy metal pollution has become a potential hazard to public health and the ecological system. Herein, molybdenum disulfide coated Mg/Al layered double hydroxide composites (LDHs@MoS2) were prepared via a simple hydrothermal method and applied for the adsorption of Cr­(VI) from a water solution. The removal capacity of Cr­(VI) on LDHs@MoS2 reached 76.3 mg/g at pH = 5.0, and the removal process relied on ionic strength and pH. The results confirmed that the uptake of Cr­(VI) on LDHs@MoS2 followed a spontaneous endothermic process. In contrast to the LDHs, LDHs@MoS2 showed excellent chemical stability, which was beneficial for practical applications. Specifically, the coexisting ions had little influence on the uptake of Cr­(VI). The interaction of Cr­(VI) with the LDHs@MoS2 composites was mainly controlled by electrostatic attraction and outer-sphere surface complexation. The findings can provide new insights into the uptake of heavy metal ions in a natural aquatic environment pollution cleanup.

Carbohydrate-supramolecular gels: Adsorbents for chromium(VI) removal from wastewater

“…The most efficient gel reaches an adsorbing capacity of 598 mg/g which is a significant improvement on other gel systems for which a maximum value of 153 mg/g has been reported. [14,16,58] In addition, the gel can be recycled up to 4 times.…”

Functionalized layered double hydroxide applied to heavy metal ions absorption: A review

“…Based on molecular simulation, the bonding energy between MgAl-LDH-phytate and metal ion is different, which results in MgAl-LDH-phytate having selective absorption [117]. The surface of MgAl-LDH coated by Molybdenum disulfide can effectively remove Cr 6+ , which is not affected by the presence of coexisting anions (K + , Na + , Ca + , Mg 2+ , Zn 2+ , and Al 3+ ) or cations [118]. The K sp (solubility product constant) follows the order of K sp (Cd(OH) 2 ), and absorption of Cu 2+ and Pb 2+ by functional groups and isomorphic substitution between Cu 2+ or Pb 2+ and Mg 2+ are easier.…”

Chemically Modified CaO/Fe3O4 Nanocomposite by Sodium Dodecyl Sulfate for Cr(III) Removal from Water

“…The initial pH of the solutions containing heavy metals affects the changes in surface charge of the adsorbent and the degree of ionization of the adsorbed heavy metal ion throughout the adsorption process [24,27]. 3 at pH values between 7 and 11 [28,29].…”