Transformative strategies for heavy metals extraction: Ionic liquid-boosted fizzy capsule for distributive solid-phase microextraction in aquatic environments

Within this work, an innovative ionic liquid-coated sulphonyl silanized graphene oxide-supported fizzy capsule- enhanced ionic liquid distributive solid-phase micro-extraction (MGO@SO3H-IL-DSPM) was successfully pre- pared for enriching and extracting lead [Pb(II)], cadmium [Cd(II)], and cobalt [Co(II)] ions from water samples. The MGO@SO3H hybrid was investigated using Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM), Zeta potential and surface area. Exploration and optimization were conducted on various parameters including solution pH, dosages of extrac- tant, volume of ionic liquid, and the type and concentration of eluent. The optimized experimental conditions for achieving high extraction efficiencies of the targeted metals were determined as follows: a mixture of Na2CO3 and NaH2PO4 (0.12 g) each, at a 1:1 M ratio); utilization of 0.03 g of MGO@SO3H nanocomposites; addition of 10 μL of ionic liquid as the extractant; pH adjustment to approximately 5 for Pb(II), and 4.18 for both Co(II) and Cd(II); and elution using HNO3 as the eluent (at a concentration of 1.5 M, with a volume of 3 ml). Under the ideal circumstances, the extraction yield efficiencies of the target metal ions in four authentic water samples were in the range (96.09 % − 100 %) for Cd(II), (99.99 % − 102 %) for Pb(II), and (99.99 % − 103 %) for Co(II), the RSDs were lower than 1.7 %. The content of Cd(II), Pb(II), and Co(II) ions in four actual samples of water were determined within the range of 1.25 – 3.75 μg/L, 6 – 15 μg/L, and 29.15 – 70 μg/L, respectively.