The aim of this study was to develop a chitosan-based magnetic adsorbent for selective and effectiveremoval of phosphate from aqueous solutions. For this purpose, Cu–chitosan/Fe3O4nanocomposite wasprepared using a facile method and characterized. The prepared adsorbent exhibited more porous surfacewith higher specific area compared to neat chitosan based on SEM and BET studies. The FTIR and EDXstudies indicated the presence of Cu(II) bonded to the adsorbent surface. Crystalline properties of theadsorbent were also studied using XRD. Experimental isotherm data were fitted to nonlinear forms ofLangmuir and Freunlich models. The maximum capacity for the modified adsorbent was calculated tobe 88 mg P2O5/g, much higher than that for neat chitosan and chitosan/Fe3O4according to the Langmuirisotherm. The adsorption by the modified adsorbent had fast kinetics and obeyed pseudo-second-orderkinetic model. Interestingly, the maximum removal efficiency for the modified adsorbent was observedin neutral pH values, pHs of natural waters. A high selectivity against natural waters common anions aswell as good regeneration ability was obtained for the introduced adsorbent.
