Lanthanide sorbent based on magnetite nanoparticles functionalized with organophosphorus extractants

Abstract

In this work, an adsorbent was prepared based on the attachment of organophosphorus acid extractants, namely, D2EHPA, CYANEX 272, and CYANEX 301, to the surface of superparamagnetic magnetite (Fe3O4) nanoparticles. The synthesized nanoparticles were coated with oleic acid, first by a chemisorption mechanism and later by the respective extractant via physical adsorption. The obtained core–shell functionalized magnetite nanoparticle composites were characterized by dynamic light scattering, scanning electron microscopy, transmission electron microscopy, thermogravimetry, infrared absorption and vibrating sample magnetometry. All the prepared nanoparticles exhibited a high saturation magnetization capacity that varied between 72 and 46 emu g−1 and decreased as the magnetite nanoparticle was coated with oleic acid and functionalized. The scope of this study also included adsorption tests for lanthanum, cerium, praseodymium, and neodymium and the corresponding analysis of their results. Sorption tests indicated that the functionalized nanoparticles were able to extract the four studied lanthanide metal ions, although the best extraction performance was observed when the sorbent was functionalized with CYANEX 272, which resulted in a loading capacity of approximately 12–14 mgLa/gMNP. The magnetization of the synthesized nanoparticles was verified during the separation of the lanthanide-loaded sorbent from the raffinate by using a conventional magnet.

Environmental implications and applications of engineered nanoscale magnetite and its hybrid nanocomposites: A review of recent literature

“…The findings suggest that dendritic nanocomposite could be potentially used as a highly effective material for the enrichment and preconcentration of europium or other trivalent lanthanides/actinides in nuclear waste management [362]. An adsorbent prepared based on the attachment of organophosphorus acid extractants to the surface of MNPs has been coated with oleic acid for adsorption of lanthanum, cerium, praseodymium, and neodymium [363].…”

Selective Recovery of Europium and Yttrium Ions with Cyanex 272-Polyacrylonitrile Nanofibers

“…A band centered at 1168 cm −1 is observed only in the PAN-272 due to the P=O stretching vibration, confirming the presence of Cyanex 272 in the membranes [35]. Finally, sharp bands centered at 959 and 815 cm −1 are assigned to P-O and P-O-C stretching vibration, that are characteristic of the organic extractant [35,36]. The results present a high homogeneity in the intensity for the different samples which indicate a homogeneous surface impregnation in the same sample and in the different modification batches.…”

“…The bonded OH vibration gives very weak and broad bands at 2700-2300 cm −1 , whereas a sharp band centered at 1672 cm −1 represent OH deformation. A band centered at 1168 cm −1 is observed only in the PAN-272 due to the P=O stretching vibration, confirming the presence of Cyanex 272 in the membranes [35]. Finally, sharp bands centered at 959 and 815 cm −1 are assigned to P-O and P-O-C stretching vibration, that are characteristic of the organic extractant [35,36].…”

Lanthanide recovery by silica-Cyanex 272 material immobilized in alginate matrix

“…The development and application of green adsorbents and hybrid materials for the selective removal and recovery of lanthanides have attracted enormous attention the last years (Basualto et al 2015;Ramasamy et al 2017;Iftekhar et al 2018). Alginate is a biopolymer widely used for encapsulation purposes (Tan and Ting 2014;Bertagnolli et al 2015).…”