Humic acid and nano-zeolite NaX as low cost and eco-friendly adsorbents for removal of Pb (II) and Cd (II) from water: characterization, kinetics, isotherms and thermodynamic studies

Abstract Humic acid as a green-sorbent was synthesized from marine sediments. While kaolin modified to nano-zeolite NaX. Different tools such FT-IR, SEM, EDX and XRD were applied confirm the characteristics of generated green-sorbents. factors pH, contact time, sorbent dosage, initial metal ion concentration, temperature interfering ions carefully examined used optimize batch adsorption process for Cd 2+ Pb . A small dose 100 mg required attain maximum at pH about 7, shacking time 60 min concentration 30 ppm. Also, sorption capacity on achieved in neutral medium very short implying economic feasibility process. In case humic acid, removal operated acidic 40 min. Metal remediation results evaluated by some isotherm models different temperatures. The kinetic thermodynamic variables also computed. data fitted well with linear Langmuir pseudo-second-order model favourable regulated both external mass transfer intraparticle diffusion steps over whole range concentrations, shown results. percentage four real water samples green sorbents provides good evidence two promising eco-sorbent heavy ions.