A Phosphonic Functionalized Biopolymer for the Sorption of Lanthanum (III) and Application in the Recovery of Rare Earth Elements

Abstract

Phosphonic acid functionalization of gellan gum and chitosan biopolymers was successfully performed. In the first step, the sorption was investigated using La(III) ions before testing for the recovery of rare earth elements (REEs) from pretreated industrial acidic leachate. The sorbent was characterized by Fourier-transform infrared (FTIR), scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET), and pH of zero charge (pHPZC) determination. FTIR and EDX results show efficient grafting of phosphoryl groups. The sorption was determined for the crude materials before functionalization (PGEG) and after phosphorylation (TBP-PGEG). More efficient sorption was seen for phosphorylated sorbent than for the crude composite. The sorption capacity is 0.226 mmol La g−1 for the PGEG while the value is 0.78 mmol La g−1 for the TBP-PGEG. We infer that phosphonate groups participate in the sorption. The most effective sorption is at pH = 4. The kinetic behavior was described using pseudo first-order equations (PFORE), pseudo second-order equations (PSORE), and resistance to intraparticle diffusion (RIDE). The sorption isotherms can be better represented by Langmuir and Sips equations than by the Freundlich equation. The sorbent shows high stability performance during reuse cycles with a limit on the decrease in the sorption performances and stability in the desorption performances. We have thus developed a good tool for the recovery of REEs with a selectivity higher than that of the non-functionalized components.

Green Synthesis of Zinc Oxide Nanoparticles Using an Aqueous Extract of Punica granatum for Antimicrobial and Catalytic Activity

“…The main cause of environmental pollution comes from the usage of organic dyes in the food and textile industries. In addition, these contaminants are too hazardous, causing cancer in humans and harming the environment [21,22]. For instance, tiny quantities of an organic dye of methylene blue (MB) in water can cause a variety of illnesses, including anemia due to hemolysis, irritations, and stomach problems.…”

New modified heterocyclic-magnetite chitosan nanocomposite for efficient alizarin red dye removal: adsorption analysis and antibacterial activity.

“…Recently, the research progress in the synthesis and modification of chitosan-based polymer nanocomposites has been widely developed because of their unique mechanical and physicochemical properties which strongly qualify them to undergo various environmental applications [21] [22]. For example, it was illustrated that functionalized modified chitosan nanocomposites can improve chemical stability, sorbents porosity, and adsorption capacity [23] [24] [25] [26] [27] [28].…”