Synthesis of Ternary Complex-Based Ion Imprinted Polymer Sorbent for Selective Adsorption of Lead Ions

In this study, Lead(II) ion imprinted polymer particles were synthesized by preparing ternary complex of lead imprinted ion with 4-(2-pyridilazo) resorcinol (PAR) and 4-vinylpyridine (VP) and then copolimerizing with methacrylic acid as functional monomer, Trimethylolpropane trimethacrylate (TRIM) as crosslinking agent, methanol as porogen, and benzoyl peroxide (BPO) as initiator. Polimerization was carried out by thermal method. HNO3 5 M was used to remove the template ion by shaking the polymer for 24 hours in several times to obtain leached IIP particles (Pb-IIPs). Non-Imprinted Polymers (NIPs) as control were similarly prepared without imprinted ion. In this study, two types of NIPs were made including with and without the addition of PAR ligands (NIP and NIPP). All polymer particles were characterized by spectral (FTIR), thermal (TGA-DTG), morphology (SEM), and nitrogen adsorption studies (BET). The adsorption and selectivity studies for lead ion were carried out with Pb-IIP, NIPP, and NIP. The adsorption of 20 mg.L-1 of lead(II) using 25 mg of polymer particles in the pH 6 with interaction time 90 min. Maximum adsorption capacity of leached Pb-IIP was found to be 14.3 mg.g-1. The Pb-IIPs displayed excellent selectivity againts three common divalent ions Cu(II), Cd(II), and Zn(II) with selectivity coefficient for each metal ions are 19.98, 42.15, and 42.96, respectively, showing high anti-interfere ability. The precision for the method (% RSD) to be 2,9 % for five times the replication of the adsorption measurement. A high percentage of recovery values ranging from 97-103 %, indicating its accuracy.