High performance of phytic acid-functionalized spherical poly-phenylglycine particles for removal of heavy metal ions

Abstract In the present work, a novel material consisting of phytic acid-functionalized poly-phenylglycine (PA-PPG) was successfully synthesized through radical polymerization and used for the removal of heavy metals ions from water. Microscopic images revealed the formation of homogenous particles in aggregated form. The chemical composition of the PA-PPG was examined using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. The influence of various experimental parameters such as solution pH, alkaline metals, and initial concentration of Cu, Pb, Cd ions on the removal efficiency of PA-PPG was assessed by using absorption atomic spectroscopy (AAS). The PA-PPG sample exhibited high maximum adsorption capacity of 90.5, 732.4, and 216 mg/g for Cu, Pb, and Cd ions, respectively. The PA-PPG demonstrated a pH-dependent adsorption with a maximum adsorption capacity achieved at pH 5.2. The Langmuir and Temkin models described well the adsorption isotherm data and a probable adsorption mechanism based on complexation and electrostatic attraction was proposed. Moreover, the developed PA-PPG can be reused for four cycles without any apparent loss of its adsorption capacity. The obtained results prove the efficiency of phytic acid, validate and promote the idea of using an active molecule to enhance the capacity of poly-phenylglycine for environmental remediation.