Removal of iron from water using iron oxide coated hollow polymethylmethacrylate microspheres

Abstract

Functional hollow poly (methyl methacrylate) microspheres (HPMM) coated with iron oxide (FHPMM) were synthesized as a highly efficient material for the removal of iron from water. The material was characterized by using Optical Microscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), and Vibrating Sample Magnetometer (VSM). The most intriguing feature of this material is low bulk density of the order of 0.60 gm/cc for uncoated HPMM and 1.27 gm/cc for FHPMM resulting in the enhanced surface area leading to enormously high adsorption capacity revealed from the adsorption isotherm study compared to the conventional iron oxide coated sand used for separation of iron from water. Optimum conditions of adsorption were determined by carrying out batch experiments. Under batch studies, investigation of the effect of various operational parameters such as initial metal ion concentration, pH, and contact time were carried out. Kinetic studies showed that the adsorption equilibrium time was reached within 30 min and the adsorbent showed a high affinity for Fe (II) ions at a pH value of 7.5. The adsorption isotherm was well fitted by the Langmuir model. The maximum adsorption capacity of FHPMM for iron was 2.322 mg/g. Based on the results, this low-density high-performance material can be advocated as a superior adsorbent to replace the conventional iron oxide-coated sand used in water purification systems.