Tri-Metallic Composite Incorporated Polyacrylamide Hydrogel for Removal of Fluoride ions from Aqueous Media

Abstract

Attached

Fluorine exists as reactive fluorides in nature owing to its high electronegativity originating from either natural or human activities. Trace amounts o f fluoride can exist in drinking water and essentially in all crops. Even though fluoride in low quantities is an indispensable micro-nutrient, which is expended on strengthening o f bones and teeth, an excessive amount o f fluorides is highly toxic which could cause skeletal and dental fluorosis, cancers, brittle bones, Alzheimer’s syndrome, infertility, and thyroid disorder. Therefore, current study was designed to implement tri-metal incorporated polyacrylamide (PAM) gel for removal o f excess amounts o f fluoride ions from aqueous media. The need for novel polymeric materials to remove and separate toxic heavy metal ions and fluoride ions through complexation and ion exchange mechanism has increased. Therefore, our attention has been drawn to develop a novel tri metal loaded PAM to achieve high defluoridation efficiency. A novel iron-cerium-lanthanum bimetallic composite was synthesized by a co-precipitation method to enhance fluoride removal efficiency. Tri-metallic composite was incorporated into a PAM. PAM have been used as the matrix material o f the fluoride removal system. The adsorption process was highly pH-dependent, and tri-metal incorporated PAM has shown maximum adsorption towards F' ions with 107.52 mg/g at pH 7.0 and 301 K. The adsorption isotherm could be well described by Langmuir isotherm model with 0.99 for R2. The adsorption rapidly occurred in the initial 1 hour and adsorption equilibrium was established within 5 h. The pseudo second order rate could be well fitted with 0.99 for R2 to fluoride adsorption kinetics. Fluoride ions adsorption is considerably unchanged when chloride ions present in aqueous media. However, presence o f sulphate and bicarbonate ions in water body might affect adsorption of fluoride ions in aqueous media. The Fourier transform IR spectroscopy, X-ray Diffraction (XRD) and atomic absorption spectroscopic methods were used to characterize and analyze trimetalic composite for selectively removal o f fluoride ions from aqueous media.