Preparation of diglycolamide polymer modified silica and its application as adsorbent for rare earth ions

Abstract

Three novel diglycolamide monomers were synthesized and polymerized on silica. The diglycolamide polymer grafted silica were used as adsorbents for rare earth ions. The effects of acid concentration, structure of monomer, initial solution concentration, contact time and coexisting ions on adsorption of rare earth ions were investigated in detail. It was shown that the adsorption capacity increased with increasing acid concentration. Three adsorbents exhibited selectivity for middle and heavy rare earth over light rare earth in different extent. The adsorbent prepared from the monomer having the largest alkyl substituent showed the lowest adsorption capacity but the highest selectivity for different rare earth elements (REEs). Adsorption data were well fitted to the Langmuir isotherm and pseudo-second-order models. The presence of high concentrations (100 fold) of coexisting metal ions, K(I), Cr(II), Cu(II) or Fe(III), does not decrease the adsorption for rare earth ions seriously.

A Modern Computer Application to Model Rare Earth Element Ion Behavior in Adsorptive Membranes and Materials

“…In this program, the user will be able to choose the appropriate kinetic model and adsorption mechanism model for the adsorptive materials and membranes, such as the Lagergren pseudo-first order, pseudo-second-order and Elovich kinetic models and the intraparticle diffusion model, the diffusion-chemisorption model, and the Boyd model to study the various mechanisms. In this work, the experimental results found throughout the literature [ 62 , 63 , 64 , 65 ] were compared with the theoretical data predicted by means of the mentioned models. The user could enter the parameters, such as the adsorption capacity ( q t ) of REE ions at contact time ( t ).…”

“…The synthesized Lu (III) IIP had a good selective recognition ability for Lu (III) ion, compared with other ions. Liu et al [ 64 ] have synthesized the new materials for REE ion adsorption, based on diglycolamide polymer-grafted silica. The prepared materials were used for separation of Eu (III) ions from solutions with other metal ions, such as K(I), Cr (II), Cu (II) or Fe (III).…”

“…The operation of the proposed computer application was verified on the basis of sample experimental data of the adsorption process of selected REE ions on various types of adsorption materials. For this purpose, experimental data presented in 4 different publications were used [ 62 , 63 , 64 , 65 ]. The first type was Ce (III) ion imprinted materials based on 2-hydroxyethyl methacrylate (HEMA) and N-methacryloylamido antipyrine (MAAP) as functional monomers [ 62 ].…”

“…The second analyzed material was synthesized as a Lu (III)-ion-imprinted polymer, based on Lu (III)-4-vinylpyridine-acetylacetone complex as a functional monomer and ethylene glycol dimethacrylate as a crosslinker [ 63 ]. The third type of adsorption material has been synthesized by Liu et al [ 64 ] in the form of diglycolamide polymer-grafted silica. The last type of adsorbents [ 65 ] were the imprinted mesoporous cellulose nanocrystals films (IMCFs).…”

Rare Earth Elements Uptake by Synthetic Polymeric and Cellulose-Based Materials: A Review

“…Synthetic organic polymers supported on silica have been studied for RE uptake. Poly-diglycolamide supported on silica particles shows similar capture capacities for REEs to commercial ion exchange resins, although it seems more selective toward REEs at low pH values [ 35 ]. Another silica-based material with polyacrylamide also shows similar capture capacities for Tb (III) to commercial resins at pH 6.0 [ 36 ].…”