Preparation magnetic cassava residue microspheres and its application for Cu(II) adsorption

A novel adsorbent, magnetic cassava residue microspheres, was prepared by using an inverse emulsion method with cassava residue used as raw material, acrylic acid and acrylamide used as grafted monomer, and methyl methacrylate (MMA) used as dispersing agent; and characterized by scanning electron microscope, transmission electron microscope, particle size analyzer, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The results showed that the acrylic acid and acrylamide was successfully introduced into the adsorbent, and exhibited a good dispersion with uniform particle size distribution. The average particle size of the magnetic cassava residue microspheres was 206 nm, and the saturation magnetization is 11.9 emu/g. The dispersing agent MMA formed a thin film on the microspheres surface, resulting in good sphere shape and promoting the dispersion of microspheres. When used to remove Cu (II) from an aqueous solution, the adsorption capacity of magnetic cassava residue microspheres was remained at 110.5 mg/g after 6 times used. The adsorption process was conformed to a Frundlich isotherm and a pseudo-second-kinetic-order model, which was spontaneous and endothermic in nature.