Removal of Pb(II), Cd(II), Cu(II), and Zn(II) by hematite nanoparticles: effect of sorbent concentration, pH, temperature, and exhaustion

Abstract

Nanoparticles offer the potential to improve environmental treatment technologies due to their unique properties. Adsorption of metal ions (Pb(II), Cd(II), Cu(II), Zn(II)) to nanohematite was examined as a function of sorbent concentration, pH, temperature, and exhaustion. Adsorption experiments were conducted with 0.05, 0.1, and 0.5 g/L nanoparticles in a pH 8 solution and in spiked San Antonio tap water. The adsorption data showed the ability of nanohematite to remove Pb, Cd, Cu, and Zn species from solution with adsorption increasing as the nanoparticle concentration increased. At 0.5 g/L nanohematite, 100 % Pb species adsorbed, 94 % Cd species adsorbed, 89 % Cu species adsorbed and 100 % Zn species adsorbed. Adsorption kinetics for all metals tested was described by a pseudo second-order rate equation with lead having the fastest rate of adsorption. The effect of temperature on adsorption showed that Pb(II), Cu(II), and Cd(II) underwent an endothermic reaction, while Zn(II) underwent an exothermic reaction. The nanoparticles were able to simultaneously remove multiple metals species (Zn, Cd, Pb, and Cu) from both a pH 8 solution and spiked San Antonio tap water. Exhaustion experiments showed that at pH 8, exhaustion did not occur for the nanoparticles but adsorption does decrease for Cd, Cu, and Zn species but not Pb species. The strong adsorption coupled with the ability to simultaneously remove multiple metal ions offers a potential remediation method for the removal of metals from water.

Competitive Adsorption of Cadmium(II) and Mercury(II) Ions from Aqueous Solutions by Activated Carbon from Xanthoceras sorbifolia Bunge Hull

“…Langmuir isotherm model Freundlich isotherm model q m (mg⋅g − C, t = 300 min, revolution rate = 200 revolutions⋅min −1 , 0(Cd(II)) = 0.005 mol⋅L −1 , and 0(Hg(II)) ranged from 0.0035 to 0.0065 mol⋅L −1 ). similar reported adsorbents [26]. XLAC has considerable potential for the removal of Cd(II) and Hg(II) ions from wastewater, with stronger affinity for Cd(II) ions.…”

A Theoretical Study on the Inclusion of Fe, Cu, and Zn in Illite Clays

“…Of note is that in all positions, 3 Journal of Nanomaterials the highest oxidation state of the metals (Fe 3+ , Cu 2+ , and Zn 2+ ) is the most favoured for being incorporated into the illite structure. This result is of interest because it implies a major availability of those elements in the illite structure for being extracted, which agrees with experimental results of desorption of those metals [5,14,19,21,29]. In this way, from now on the discussion of the results will be mainly focused on the inclusion of the highest oxidation states of the metals.…”

“…Journal of Nanomaterials polluted soils based on the use of plant is phytoremedation [12,18]. Phytoremediation is both an efficient and an economically feasible method that can be used for the removal of heavy metals and radionuclides as well as for organic pollutants such as polynuclear aromatic hydrocarbons, polychlorinated biphenyls, and pesticides [12,18,19]. Terrestrial plants have the capacity of adsorbing heavy metals present in the soil [14,20].…”

Development of chemically active metal oxide composite nanofiber filters for water treatment

“…pH-dependent sorption was assessed from pH 6 to 8 at relatively low concentrations of metals/metalloids compared to those used in isotherms (7.4 mg/L AsO4 3-, 6.7 mg/L Generally, however, the pH-dependent behavior of AsO4 3-, CrO4 2-, and Cu 2+ in systems with PAN/Fe2O3 and PAN/Fe2O3@Fe2O3 is consistent with that previously observed with these metals in more traditional iron oxide sorbent systems [188][189][190]201,202]. For Pb 2+ , however, a clear increase in adsorption is often reported with increasing pH on iron oxides [203,204], behavior that was not pronounced on our composites. Again, this may relate to the ability of PAN to bind Pb 2+ , particularly at higher pH, providing further evidence that Fe2O3 immobilized in or on PAN nanofibers may exhibit distinct reactivity from unsupported hematite under some circumstances.…”