Highly selective and efficient heavy metal capture with polysulfide intercalated layered double hydroxides

Abstract

Intercalation of polysulfides into LDHs forms layered composites that can separate Hg2+, Ag+ and Cu2+ from mixed ions with high selectivity and capacity.

Highly selective and efficient removal and extraction of heavy metals by layered double hydroxides intercalated with the diphenylamine-4-sulfonate: A comparative study

“…According to the results given in Table 5, the adsorption ability of DPA-LDH toward Pb 2+ and Cu 2+ is higher than that of the other ions. As shown in Table 5 Table 6 shows that the obtained K d values for DPA-LDH are higher than those that were reported for previous sorbents such as metal-organic frameworks [6], dodecyl sulfate based intercalated-LDHs [28], carbonate based LDHs [29], sulfide based intercalated-LDHs and materials [10,40,41], polymers [42,43], magnetic nanoparticles [44,45], ion imprinted polymers [46], layered hydrogen metal sulfides [47], and zeolites [48]. The comparison of the q m values of DPA-LDH with the same values of other sorbents presented in the literature (Table 6) for metal ions removal is indicative of the higher efficiency of DPA-LDH for the removal of heavy-metal ions.…”

A new, low-cost adsorbent: Preparation, characterization, and adsorption behavior of Pb(II) and Cu(II)

“…Structurally [38], LDHs have the characteristics of anion exchange, which make them adsorb mainly inorganic pollutants such as phosphate [39], borate [40], fluoride [41], and other organic anions [42,43] as well as metal ions in the form of anionic Cr (VI) [44]. The LDH-based composites materials which were prepared by intercalating certain chemical compounds such as crown ether [45], EDTA [46], nitrilotriacetate [47], chromotropic acid [48], aurintricarboxylic acid [49], and polysulfides [50] can adsorb metal ions. However, from the industry side, the dream of these LDH-based adsorbents really used in industry for adsorbing metal ions, is quite hard to realize, because the used guest anions are very expensive.…”

Characteristics, Preparation Routes and Metallurgical Applications of LDHs: An Overview

“…Compared to LDH alone as an adsorbent, LDH-containing hybrids exhibit enhanced adsorption tendency of toxic pollutants due to their improvement in surface area [100][101][102][103], higher anion exchange tendency [104,105], better stability [106], increase in chelating and binding sites [107], excellent selectivity for different metal ions [108][109][110], low toxicity and ease in separation and reusability when hybridized with magnetic particles [111][112][113]. As a result of these superior properties, they are up-and-coming adsorbents for wastewater treatment.…”