Synthesis and application of iron/copper bimetallic nanoparticles doped natural zeolite composite coupled with ultrasound for removal of arsenic (III) from aqueous solutions

Abstract

The removal of arsenic (III) from aqueous solutions was investigated using zeolite supported by nano zero-valent iron/copper bimetallic composite (Z-nZVI/Cu) coupled with Ultrasound. The bimetallic nZVI/Cu nanoparticles incorporated into zeolite were prepared using an ion exchange method and were characterized using transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy and Brunauer–Emmett–Teller. The results of the analyses showed that ZVI/ Cu nanoparticles were successfully distributed on the zeolite. The highest As (III) removal efficiency by ultrasonic process coupled with Z-nZVI/Cu was obtained at pH of 5, As (III) concentration of 1 mg/L, catalyst dosage of 0.3 mg/L, ultrasonic frequency of 80 kHz and reaction time of 60 min. The experiments showed that the As (III) removal efficiency was decreased by increasing the initial pH and As (III) concentration, but it was increased by increasing the catalyst dosage and ultrasonic frequency. The results of the comparative experiments showed that the presence of the ultrasonic process in the solution containing Z-nZVI/Cu is led to increasing the removal of As (III) by dispersing the nanoparticles and increasing the specific surface area, as well as cleaning the catalyst surface and improving the transfer of pollutant mass between bulk solution and catalyst surface. Further study on the treatment of real water sample confirmed the applicability of the ultrasonic system coupled with the catalyst in the removal of As (III). This study showed that the ultrasonic process coupled with Z-nZVI/Cu can be effectively used to remove As (III) from aqueous solutions. © 2019 Desalination Publications. All rights reserved.