Application of aluminosilicate residue-based zeolite from lithium extraction in water treatment

In a previous study, the Na-P1 type zeolites were synthesized from aluminosilicate residues using an efficient and cost-effective process, exhibiting an excellent adsorption capacity for Ca 2+ in comparison to commercial zeolites 13X and A. Building upon this, the current study evaluates their performance for the adsorption of various elements, including Ca 2+ , Mg 2+ , and NH 4 + . The objective was to evaluate the performance of the Na-P1 type zeolites for the adsorption of various elements, including Ca 2+ , Mg 2+ , and rare earth elements, with a particular emphasis on the adsorption kinetics and water hardness removal in comparison to commercial zeolite A. The results demonstrated that the Na-P1 zeolite exhibited a satisfactory sorption capacity for Ca 2+ and NH 4 + ions (66 mg/g), while displaying a relatively lower effectiveness for the sorption of Mg 2+ ions (5.6 mg/g). The Langmuir model is particularly well suited to the sorption of Ca 2+ , while the Freundlich model is more appropriate for Mg 2+ . Both models demonstrated satisfactory representation of NH₄ ⁺ sorption. Moreover, the pseudo-second-order kinetic model provides an excellent description of the Ca 2 ⁺ and Mg 2 ⁺ sorption processes, while both models effectively describe the NH₄⁺ adsorption kinetics. Additionally, Na-P1 zeolite was observed to effectively reduce water hardness from 322 to 63 mg CaCO₃/L at temperatures of 10, 20, and 38°C, and to 18 mg/L at 58°C. These findings suggest that Na-P1 zeolite has promising potential for applications as a water softening agent. Regarding metals and rare earths, the Na-P1 zeolite demonstrated noteworthy sorption efficiencies for Cd 2+ (138 mg/g), Ce 3+ (209 mg/g), Cr 3+ (56.2 mg/g), and Cu 2+ (60.5 mg/g). However, it demonstrated lower sorption efficiencies for Co 2+ , Mn 2+ , Ni 2+ and Dy 3+ (below 16 mg/g). The findings illustrate that Na-P1 zeolites are effective for the adsorption of diverse elements, offering a promising avenue for the sustainable transformation of industrial waste into valuable materials for environmental applications. • Zeolite Na-P1 synthesized from aluminosilicate residue was used for water treatment. • Zeolite Na-P1 demonstrated a high affinity for Ca 2+ and NH 4 + sorption. • Zeolite Na-P1 shows promising potential for effective applications as water softening agent. • Zeolite Na-P1 showed notable sorption for: Cd 2+ , Cr 3+ , Cu 2+ and Ce 3+ . .