Simultaneous Removal of Multiple Heavy Metal Ions from River Water Using Ultrafine Mesoporous Magnetite Nanoparticles

Abstract

The exploration of simultaneous removal of co-existing or multiple pollutants from water by the means of nanomaterials paves a new avenue that is free from secondary pollution and inexpensive. In the aquatic environment, river water contains a mixture of ions, which can influence the adsorption process. In this respect, removing heavy metal ions becomes a true challenge. Here, four heavy metal ions, namely, Pb 2+ , Cd 2+ , Cu 2+ , and Ni 2+ , have been successfully removed simultaneously from river water using ultrafine mesoporous magnetite (Fe 3 O 4 ) nanoparticles (UFMNPs) based on the affinity of these metal ions toward the UFMNP surfaces as well as their unique mesoporous structure, promoting the easy adsorption. The individual removal efficiencies of Pb 2+ , Cd 2+ , Cu 2+ , and Ni 2+ ions from river water were 98, 87, 90, and 78%, respectively, whereas the removal efficiencies of the mixed Pb 2+ , Cd 2+ , Cu 2+ , and Ni 2+ ions were 86, 80, 84, and 54%, respectively, in the same river water. Thus, the data clearly indicate the complex removal of heavy metal ions in multi-ion systems. This study has demonstrated the huge potential of UFMNPs to be effective for their use in wastewater treatment, especially to simultaneously remove multiple heavy metal ions from aqueous media.

Spectroscopic and Microscopic Analyses of Fe3O4/Au Nanoparticles Obtained by Laser Ablation in Water

“…Hence, all the bimetallic material can be completely separated by magnetic attraction from the aqueous environment wherein it is dispersed. In the literature [26], ultrafine Fe 3 O 4 nanoparticles were employed to remove heavy metal ions from contaminated waters, thanks to their excellent adsorption performance. In a similar way, the magnetite nanoparticles obtained by laser ablation could act as adsorbents for the laser-ablated gold nanoparticles, forming a mixed bimetallic colloidal suspension.…”

“…In addition, it is possible to remove all the bimetallic material, including the possible load of adsorbed ligands, from the solvent and transport them thanks to the use of a magnetic field. In this regard, the presence of iron oxide gives the bimetallic colloid new possibilities for the adsorption of ligands, in addition to those inherent to gold nanoparticles, and also for removal of them from the aqueous environment, especially with regard to organic pollutants [25] and heavy metals [26]. Finally, our bimetallic colloids exhibit plasmonic properties, in addition to magnetic ones, due to the presence of gold nanoparticles, which allow application of the SERS technique for sensoristic purposes.…”

Recent Advances in Magnetic Nanoparticles and Nanocomposites for the Remediation of Water Resources

“…Ultrafine magnetite nanoparticles (size range 4-17 nm) were generated through a co-precipitation reaction by Long et al [36] who then demonstrated the use of these nanoparticles for the removal of metal ions from river water. As part of the synthesis, surfactants were deliberately omitted.…”

Magnetic nanostructures functionalized with a derived lysine coating applied to simultaneously remove heavy metal pollutants from environmental systems

“…However, there are still some disadvantages, such as low adsorption capacity, long adsorption time, but the main disadvantage is the complicated and costly removal of the used adsorbent after the adsorption process (filtration, centrifugation), which is not economically attractive [13,18,19]. It should be noted that only a few studies on the removal of heavy metals from the real environmental systems have been carried out with different adsorbents [20][21][22][23][24][25], whereas there is only one report on heavy metal removal from real sludge suspension using chitosan-based magnetic NPs [4].…”

“…Other studies mainly focus only on metal removal from river water [20] or (industrial) wastewater [21,22] using magnetic nanoparticles, and the on use of nZVI-based adsorbents for metal removal from industrial metal-rich wastewater streams [23][24][25]. It…”