GREEN SYNTHESIS OF SOME SCHIFF BASED-METAL COMPLEXES: CHARACTERIZATION, BIOCIDAL, AND THE ADSORPTION EFFICIENCY STUDIES

Abstract

The green synthesis of compounds has attracted sizable attention for its eco-friendly and sustainable approach. N-(2-hydroxybenzyldene)-2-hydroxyaniline (N2HB2HA) and its complexes with Fe(II), Co(II), Cu(II), and Mn(II) ions were synthesised using the microwave method. The synthesised compounds were tested for antimicrobial and nematocidal activity and their ability to adsorb metal ions. The compounds were characterised using melting point, solubility, FTIR, UV-Vis, and ¹H NMR spectroscopy. The solubility results of N2HB2HA showed that it became more soluble in common organic solvents when it mixed with metal ions. The compounds were also fairly stable. The FTIR spectra confirmed bidentate ligand coordination, the UV spectra of N2HB2HA showed absorption bands at 268 and 322.5 nm, and the metal complexes displayed additional bands indicating complexation. The 1H NMR spectrum reveals hydrogen bonding, metal-ligand interactions, and downfield shifts for aromatic protons. The Cu(II) complex exhibited strong antimicrobial and nematocidal properties, with low MIC values and high nematode mortality percentages, suggesting potential applications as antimicrobial and nematocidal agents. The adsorption studies tested 0.1 and 0.2 g of N2HB2HA in removing metal ions from aqueous solutions. The results showed that as metal ion concentration increased, removal efficiency decreased. However, 0.2 g of N2HB2HA increased, achieving high removal efficiency at 100 mg/L. The results of this study reveal the potential of N2HB2HA and its complexes as an efficient material for water purification and biocidal applications, respectively.