Development of bi-metal doped micro- and nano multi-functional polymeric adsorbents for the removal of fluoride and arsenic(V) from wastewater

The contamination of ground water by fluoride and arsenic has recently considerably increased, especially in some regions of India. In this context, the development of efficient adsorbents for the control of fluoride and arsenic, which are the common pollutants in wastewater, assumes significance. Herein, we describe the synthesis, characterization, and application of bi-metals (Fe and Al) doped micro- and nanoparticles based adsorbents for the removal of fluoride and arsenic(V) ions from water. The adsorbents were prepared by suspension polymerization. Fe and Al were incorporated during a polymerization step. The bi-metals doped beads (similar to 0.8 mm) thus prepared were carbonized and activated to create porous structure inside the materials. Nanoparticles (similar to 100 nm) were produced by milling of the beads, which were carbonized and activated. The adsorption tests carried out on Al/Fe-doped adsorbents revealed significant loading of those ions. The equilibrium loading of fluoride on nanoparticles based adsorbents was determined as similar to 100 mg/g corresponding to the aqueous phase concentration range of 0-90 ppm, whereas that of arsenic(V) was determined as 40 mg/g corresponding to the range of 0-70 ppm. The methodology adopted in this study is a step towards developing multi-functional adsorbents for the removal of different types of solutes from wastewater. (C) 2011 Elsevier B.V. All rights reserved.