Retrieval of Cu 2+ and Cd 2+ ions from Aqueous Solutions Using Sustainable Guar gum/montmorillonite Nanocomposite Films: Effect of Temperature and Adsorption Isotherms

Uncontrolled or improperly managed wastewater is considered toxic and dangerous to plants, animals, and people, as well as
negatively impacting the ecosystem. In this research, the use of we aimed to prepare polymer nanocomposites (guar gum/
polyvinyl alcohol, and nano-montmorillonite clay) for eliminating heavy metals from waterbased systems, especially Cu 2+ and Cd 2+
ions. The synthesis of nanocomposites was done by the green method with different ratios of guar gum to PVA (50/50), (60/40),
and (80/20) wt%, in addition to glycerol that acts as a crosslinker. Fourier-transform infrared spectroscopy (FT-IR) analysis of the
prepared (guar gum/PVA/MMT) polymeric nano-composites' structure and morphology revealed the presence of both guar gum and
PVA's functional groups in the polymeric network matrix. Transmission electron microscopy (TEM) analysis was also performed,
which verified the creation of a nanocomposite. Furthermore, theromgravimetric analysis (TGA) demonstrated the biocomposites'
excellent thermal properties. For those metal ions, the extreme uptake was found at pH 6.0 in each instance. The Equilibrium
uptake capacities of the three prepared nanocomposites were achieved within 240 minutes. The maximal capacities were found to
be 95, 89 and 84 mg/g for Cu 2+ , and for Cd 2+ were found to be 100, 91, 87 mg/g for guar gum (80/20, 60/40 and 50/50),
respectively. The pseudo-2 nd -order model with R 2 > 0.98 was demonstrated to be followed by the adsorption reaction, according
to the presented results. In less than four hours, the adsorption equilibrium was reached. Furthermore, a 1% EDTA solution could
be used to revitalize the metalion-loaded nanocomposites for several cycles. The most promising nanocomposite with efficiency
above 90% for the removal of Cu 2+ and Cd 2+ ions from wastewater was found to have a guar (80/20) weight percentage,
according to the results obtained