Removal of mercury (II) ion from the aqueous solution using a synthetic terpolymer

Abstract

The terpolymer has been prepared using the monomers p-hydroxybenzoicacid, thiourea and para-formaldehyde. Physicochemical properties of terpolymer have been investigated to explore adsorption process. The effectiveness of such a terpolymer in adsorbing mercury ion from aqueous solution containing 10 ppm Hg (II) ion has been studied as a function of agitation time, adsorbent dosage, initial metal ion concentration, and pH. Adsorption equilibrium studies are carried out in order to optimize the experimental conditions. The adsorption of mercury ion onto the terpolymer follows pseudo second order kinetic model. Adsorption data are modeled using both Langmuir and Freundlich classical isotherms. The adsorption capacity is found to be 53.48 mg/g at optimum pH of 4.5. Equilibrium time is found to be 3 h for all initial concentration studied. Desorption studies are performed with NaCl and show ion exchange predominant for mercury ion adsorption. The adsorbent is found to be both effective and economically viable.