Removal of arsenic contaminants using a novel porous nanoadsorbent with superior magnetic recovery

• Main Authors: Sen Lin, Junjie Jin, Shuying Sun, Jianguo Yu
• Format: Article
• Language: English
• Published: Elsevier 2020-11-01
• Series: Chemical Engineering Science: X
• Subjects: Arsenic; Magnetic nanoparticles; Adsorption; Magnetic recovery; Superparamagnetism
• Online Access: http://www.sciencedirect.com/science/article/pii/S2590140020300150

Novel porous and magnetic iron oxide nanoparticles (PMNPs) with good magnetic properties were synthesized through a simple sol–gel method and exhibited excellent adsorption performance for aqueous arsenic contaminants as well as magnetic recoverability. Hysteresis loop analysis confirmed that the PMNPs were typical superparamagnetic material with a ultrahigh magnetic saturation (Ms) of 94.77 emu/g, which allowed their quick and complete recovery even under magnetic fields less than 0.25 T. The kinetics and isotherms results confirmed that adsorption equilibrium could achieved in 30 min and the saturated adsorption capacities for As(III) and As(V) exceeded 0.64 and 0.76 mmol/g at 30 °C. The effects of initial pH and diverse co-existing ions demonstrated that the optimal conditions for arsenic removal were closely related to the PMNPs surface charge distribution and the electron density of As(III) and As(V). In addition, after 10 adsorption–desorption cycles, PMNPs still held more than 80% of the primal arsenic adsorption capacities.