Analytical application of polyurethane foam functionalized with quinolin-8-ol for preconcentration and determination of trace metal ions in wastewater

Quinolin-8-ol-bonded polyurethane foam (Ox-PUF) was synthesized by coupling the polyurethane foam matrix with oxine through an azo (-N=N-) group. The chromatographic retention behavior of Ag+, Pb2+, and Al3+ onto the Ox-PUF was studied. The extraction of Ag+, Pb2+, and Al3+ was accomplished within 15–20 min at pH ranges of 1–4, 4–6, and 6–12, respectively. The kinetics and thermodynamics of the sorption of tested metal ions onto Ox-PUF have been studied. The average values of ΔH, ΔS, ΔG; k1, k−1, k′, and t1/2 at 298 K were −28.7 kJ/mol, 210.1 J/(mol K), −6.74 kJ/mol, 0.095, 0.01, 0.113, and 7.184 min, respectively. The sorption capacities of the Ox-PUF were 0.16, 0.07, and 0.59 mmol/g for Ag+, Pb2+, and Al3+, correspondingly. The proposed method has been successfully applied to the preconcentration and removal of tested metal ions from wastewater. Recoveries between 80 and 99% were obtained (RSD ∼ 7).