Defluoridation of Bore Well Water Using Combustion Derived Nanocrystalline Magnesium Oxide

Abstract

Nanocrystalline MgO powder has been prepared through combustion route using magnesium nitrate as oxidizer and glycine as fuel; the combustion derived MgO powder has been characterized using XRD, SEM, surface area and porosity measurements. The powder XRD pattern confirms the crystallinity and phase purity of the as-made powder. The scanning electron microscope (SEM) results reveal that the combustion derived powder is an agglomeration of fine particles. The particle size of the powder is found to be in the range of 12-23 nm with a large surface area of 107 m².g⁻¹. The as-made MgO is used for defluoridation of ground water samples with stirring time (5–60 min), adsorbent quantity (0.05–0.3 g.L⁻¹) and pH (5–9) as experimental parameters. It is found that 92% and 97% of fluoride, respectively, could be removed using 0.15 g of MgO from 10 ppm of synthetic fluoride solution and standard sodium fluoride solution. In this technique 90% minimization of sludge could be achieved. It is also observed that the regeneration of adsorbent with NaOH (15 mL of 0.1 N NaOH for 0.5 g of sludge) solution gives better results than HCI (15 mL of 0.1 N HCI for 0.5 g of sludge) solution.

Keywords:

• Combustion synthesis
• Nanocrystalline MgO
• Bore well water
• Defluoridation