Graft copolymerization of acrylamide onto Hyphaene thebaica fiber and its performance for removal of heavy metals ions from aqueous solutions

Abstract

Microwave assisted preparation of Hyphaene thebaica fibre grafted with polyacrylamide (Cell-g-PAA) was carried out using microwave radiation and ammonium persulfate as initiator. The preparation was optimized in terms of percentage grafting by varying the microwave irradiation time, monomer (acrylamide) concentration and initiator concentration. The grafted product has been characterized using the following techniques; FTIR spectroscopy, SEM morphology study and X-ray diffraction (XRD). The application of the grafted product as adsorbent for removal of some metal ions from aqueous solutions has been investigated. Equilibrium data revealed that Langmuir isotherm model fitted better than Freundlich isotherm model. The adsorption capacities were 186 mg/g, 63 mg/g and 52 mg/g for lead, copper and cadmium ions respectively. The adsorbent could be used for removal Pb²⁺, Cu²⁺ and Cd²⁺ from aqueous solutions.

Keywords: Hyphaene thebaica, polyacrylamide, microwave, ammonium persulfate, adsorbent