Akaganeite nanorods decorated graphene oxide sheets for removal and recovery of aqueous phosphate

The increased amount of phosphate in water results in the depletion of dissolved oxygen levels and becomes detrimental to aquatic organism. The waste generated from industries contains large quantity of phosphates and needed effective treatment before reaching to the fresh water. In this study we report synthesis of a nanocomposite containing akaganeite nanorods (beta-FeOOH) and graphene oxide sheets (GO) via chemical route and used as a low-cost potential adsorbent for removal of phosphate dissolved in the water. In the presence of graphene oxide beta-FeOOH nanorods showed enhanced aspect ratio of rods from 5 to 7. The influence of adsorbent dose, adsorption time, solution pH, and initial phosphate concentration on the phosphate removal capacity were studied. The second order kinetics model fitted better compare to the first and solid diffusion model. The adsorption isotherm was best fitted with Langmuir model compare to Freundlich isotherm indicates formation of monolayer of phosphate on the surface of adsorbent. The beta-FeOOH nanorods/GO nanocomposite showed maximum phosphate adsorption capacity 45.2 mg/g at pH 7 and room temperature 30 degrees C.