NOVEL APPROACH FOR COLLECTING MICROALGAE IN WATER TREATMENT USING MAGNETIC NANOCOMPOSITES BASED ON BIOPOLYMER EXTRACTED FROM GRAPEFRUIT PEEL

Abstract

In this work, magnetic nanocomposites were produced by incorporating cobalt superparamagnetic (CoFe2O4) nanoparticles into the biopolymer matrix which was extracted from grapefruit peel. In which, the magnetic nanoparticles were prepared by co-precipitation approach and the nanocomposite formation was carried out with the support of ultrasonic waves. The obtained biopolymer, nanoparticles and nanocomposites were characterized by Fourier transform infrared (FT-IR) while nanoparticles and nanocomposites were further characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). Finally, the capability to collect the Tetraselmis sp. microalgae using the achieved superparamagnetic nanocomposites was assessed and effects of various factors including material weight, stirring speed and stirring time on the recovery yield were also investigated. It was found that a recovery yield of higher than 90% was attained when using the nanocomposites at the concentration of 4 g/L. In addtition, the highest efficiency was reached in the case the coagulation was done by stirring at 200 rpm for 3 mins and the flocculation was performed by slow stirring at 50 rpm for 2 mins