Feasibility of Eu3+ and Ti4+ Sorption Using Amine Functionalized Poly Acrylate hydrogel/nano Silica from Monazite Waste Aqueous Solution: Kinetic and Equilibrium Aspects

Abstract The polyacrylate /nano silica (AFPA/NS) material is a newly engineered composite with modified amine density, integrated nanosilica, and a tailored pore structure designed specifically to remain stable under the ultra-low pH conditions of monazite raffinate. It is considering a novel composite material to use for sorption Eu(III) and Ti(IV) ions. Batch sorption behavior of these ions is investigated in terms of equilibrium time, mass of adsorbent, Eu(III)and Ti(IV) concentration, and pH of solution. The sorbent could absorb Eu(III) and Ti(IV) from an acidic monazite waste solution. The experimental findings indicated optimal loading capacity at pH of 0.5 with 15 min for Europium and pH of 4 with 60 min for titanium. The sorption capacity reaches its greatest of 202.08 and 125.7 mg/g for Europium and Titanium, respectively, at 298 K. The pseudo-second order kinetic model, suggesting the involvement of a chemisorption process, and the Langmuir isotherm describe the experimental data well. The values of the thermodynamic parameters proved that the adsorption process of Eu(III)and Ti(IV) onto the prepared hydrogel could be considered exothermic (∆H < 0) and spontaneous (∆G < 0). The AFPA/NS hydrogel exhibits high chemical stability, reusability, and fast equilibration. Further, the above procedure has been successfully employed for applying real monazite waste solution, and the results revealed that the AFPA/NS hydrogel was used successfully as a promising material for the elimination and recovery of Eu(III)and Ti(IV).