Facile synthesis of Fe 3 O 4 @Cu(OH) 2 composites and their arsenic adsorption application

A directly coating method, controlled double-jet precipitation (CDJP), was developed for synthesizing magnetic Fe3O4@Cu(OH)2 composites in combination of advantages of magnetic rapid separation and satisfactory adsorption performance. The morphology and structure of the composites were analyzed by SEM, TEM, XRD, FTIR, XPS and VSM techniques. Through controlling the reaction on Fe3O4 particles, directly coating of Cu(OH)2 was successfully realized without the extra complicated procedures. The obtained Fe3O4@Cu(OH)2 consists of micro particles of size around 250 nm coated with special leaflike nanomorphologies, possessing high saturation magnetization (from 56.5 to 98.84 emu g−1). As the amount of loaded Cu increased, As(V) removal of the composites augmented from 11.11 to 35.71 mg g−1 far beyond that of reported traditional magnetic adsorbents. The adsorption isotherm was best fitted by Langmuir adsorption mode and the mechanism was mainly ascribed to the OH functionality of the Fe3O4@Cu(OH)2 composites and electrostatic attraction between As(V) species and Fe3O4@Cu(OH)2 composites. The Fe3O4@Cu(OH)2 composites is a promising candidate for treating arsenic contaminated water.