Ion Exchange Reversibility of Some Radionuclides on Zirconium Tungstosuccinate and Zirconium Tungstosalicylate at their Solid-Liquid Interfaces

Abstract

Zirconium tungstosuccinate (ZWSu) and zirconium tungstosalicylate (ZWSa) composites were synthesized by anchoring moieties of succinic acid (SuA) and salicylic acid (SaA) onto zirconium tungstate (ZW), respectively. The produced exchange composites were unambiguously characterized by TGA, DTA, XRD, and FTIR spectroscopy. Thermally stable, amorphous, highly active, and multifunctional inorganic-organic exchangers were produced. The sorption behavior of the hybrid materials for removal of some hazardous radionuclides, ¹³⁴Cs, ⁶⁰Co, and ^152+154 Eu has been studied for covering different pHs, contact time, and concentrations; capacity; 2.6, 3.14, and 4.05 meq/g were accommodated. FORM, PFORM, and PSORM equations were kinetically tested to predict the reaction mechanism. Adsorption isotherms have been constructed at different reaction temperatures (30, 40, 50, 60 ± 1°C). Adsorption of ¹³⁴Cs, ⁶⁰Co, and ^152+154 Eu on the exchangers fit to Langmuir and Freundlich isotherms. The effect of temperature on the equilibrium distribution coefficient values was also investigated, and the thermodynamic parameters were determined; the reverse order kinetics and ion exchange reversibility were moreover indicated.

Keywords:

• capacity
• ion exchange composites
• isotherms
• kinetics
• reversibility
• thermodynamics