Extraction and recovery of rare earths by chelating phenolic copolymers bearing diglycolamic acid or diglycolamide moieties

Abstract

Extraction and recovery of rare earth elements (REEs) have been studied using ion-exchange and chelating process thanks to phenol copolymeric resins. The ion-exchange and chelating resins have been prepared through an alkaline polycondensation reaction of phenolic diglycolamide derivatives with admixture of phenol, catechol or resorcinol in the presence of formaldehyde as crosslinker. The phenol copolymeric resins were fully characterized and involved in sorption experiments. The sorption experiments of rare earth elements have been investigated in different acidic conditions. Lanthanum (La), europium (Eu) and ytterbium (Yb) were chosen to represent the light, medium and heavy REEs respectively. Changes in the extraction properties of the copolymeric resins have been observed depending on the nature of chelating groups in the phenolic matrices and the extraction conditions. The results indicate that the synthesized materials are good sorbent for REEs with cation uptake capacity in the range 50-100 mg/g and in some cases above 150 mg/g.

Application of Impregnated Resins for the Recovery of Actinides from Alpha Contaminated Solid Waste

“…In the range 118 °C to about 309 °C, the weight loss was due to the decomposition of TBP, [39] while the XAD‐4 began to decompose at 321 °C. The encapsulation capacity of the micro‐capsules as calculated was approx.12.1 % for TBP and 11.8 % for T2EHDGA, [40] respectively. The TGA results also showed that the impregnated material could be used below 100 °C.…”

Terephthalaldehyde–Phenolic Resins as a Solid-Phase Extraction System for the Recovery of Rare-Earth Elements

“…The resole-type phenolic resins were studied with regard to their ion-exchange properties coming from their phenolic OH groups and/or from active chelating groups [8,9]. A variety of phenolic resins were investigated for the sorption of various heavy metals [10][11][12][13], metalloids [14], lanthanide cations [15][16][17][18][19] and radionuclides [20][21][22][23].…”

“…Those thermosetting polymers exhibit high thermal performances in comparison with conventional phenol-formaldehyde resins [29]. Recently it was demonstrated through a comparative study that resorcinol-based polymer bearing ligand exhibited higher lanthanides extraction efficiency than that of phenol and catechol-based polymers [19].…”

Selective Extraction of REEs Thanks to One-Pot Silica Hybrid Materials

“…However, the large shares of iron in typical leachates that hamper extraction require the use of highly selective and mechanically stable extraction materials [11]. Diglycolamic acid derivatives in various support materials were shown to fulfill these criteria [12][13][14][15][16][17][18][19]. Modified silica hybrid materials (SHMs) are an especially promising candidate for the recycling of REEs [20][21][22].…”