Adsorptive removal of fluoride from water samples using Zr–Mn composite material

Abstract

The toxicity of fluoride to mankind is very high. Thus there has always been need to treat fluoride contaminated water samples for its removal to make it safe for human consumption. A novel and efficient analytical method for the removal of fluoride using Zr–Mn composite material has been developed for water samples. The adsorption was confirmed by the use of various techniques like X-ray diffraction (XRD), Brunauer, Emmett and Teller (BET) and FTIR. The key parameters that influence analyte i.e. fluoride removal were investigated and optimized. Under the optimized conditions of the adsorbent dose 1.2g/50mL, pH 7, temp 29°C and the contact time 145min, an excellent fluoride removal up to 90% was achieved. The proposed material has successfully been applied to the removal of fluoride in different aqueous solutions having a broad concentration range of fluoride. The effectiveness of the sorption process on the adsorbent (Zr–Mn composite material) was verified by testing it on natural waters loaded with the proposed fluoride. The reproducibility of the method was validated by removing fluoride in various water samples by the proposed method in a different laboratory under the same condition. The simplicity of the proposed fluoride removal material, very high removal efficiency, short time and the use of safe chemicals demonstrate the high potential of the proposed method for routine fluoride removal from water samples. The process of adsorption by Zr–Mn composite material followed Freundlich as well as Langmuir isotherms but is favorable to Freundlich isotherm that provides best fit to the experimental data. The results obtained showed that adsorption on the Zr–Mn composite material could be an effective method for the removal of fluoride.