One-pot facile approach to design an efficient macro-porous polymeric matrix to remediate Hg(II)and Pb(II) from aqueous medium and its performance evaluation study by mathematical modelling.

ABSTRACT

In the present scenario discharge of heavy-metal ions into water bodies is a global threat that is causing serious health hazards even in low concentrations. Thus, in order to remediate the heavy-metal [Hg(II) and Pb(II)] toxicity, an organic-inorganic hybrid functional porous metallo-polymeric network i. e, poly(Zirconyl methacrylate-co-1-vinyl imidazole) (pZrVIm) was fabricated via one-pot facile synthesis approach. The pZrVIm architecture has shown high removal efficiency for Hg(II) and Pb(II) aqueous medium even in extremely low quantities. Advanced instrumental techniques were used to characterize the structural and morphological characteristics of pZrVIm. Different experimental variables i.e., reaction time, pH, initial feed concentration, co-ion effects etc. were explored to examine adsorption behaviour. The maximum adsorption capacities (qmax) of pZrVIm5 were calculated as 168.06 and 162.34 mg g-1 for Hg(II) and Pb(II) respectively by the Langmuir isotherm model. Data from isotherms showed that monolayer adsorption on a homogeneous surface is the rate-limiting stage and followed pseudo-second-order kinetic process. The Artificial Neural Network (ANN) modelling was used to validate kinetics and isotherm data which revealed high accuracy of the model with correlation coefficient values (R = 0.99). Various types of isotherm models such as Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, Redlich-Peterson, Toth and Koble-Corigen have been studied to determine the adsorption phenomena. The pore diffusion model revealed breakthrough time of 91 h and 84 h, Hg(II) and Pb(II) with the feed concentration of 15 mg L-1 respectively. The study revealed that pZrVIm5 has great potential for heavy metal ions remediation for water treatment.