Journal Article

Preparation of magnetic composites and their dimethyl arsonic acid adsorption performances

Ma, Xiao-Yan, Xamsiya, Nurmamat, Xie, Qing-Qing, Hadiya, Ablat, Zhao, Zhi-Xi

2023

Overview

Dimethyl arsonic acid, the most common organic arsenic pollutant, is widely present in the environment and seriously threatens the safety of drinking water. Syntheses of magnetite, magnetic bentonite, and magnetic ferrihydrite via hydrothermal methods, and the magnetic composites were examined using XRD, BET, VSM, and SEM. SEM images revealed that many monodispersible pellets were attached to the surface of magnetic bentonite. The magnetic ferrihydrite contained abundant pores and had a rich pore structure, which expanded the specific surface area of the original magnetite. The specific surface areas of the magnetic bentonite and magnetic ferrihydrite were 65.17 and 220.30 m 2 ·g −1 , respectively. The adsorption kinetics and adsorption isotherms of dimethyl arsonic acid on magnetic composites were studied. The adsorption of dimethyl arsonic acid on the magnetic composites conformed to the pseudo-second-order model and Freundlich isothermal adsorption model. By comparing the isotherms of the adsorption of dimethyl arsonic acid by the magnetic composites at pH values of 3, 7, and 11, respectively, it was found that the adsorption of dimethyl arsonic acid was the greatest at neutral pH of 7. The adsorption mechanism was analyzed via zeta potential determination, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The zeta potential results revealed that magnetic bentonite electrostatic activity occurred with dimethyl arsonic acid, and the magnetic ferrihydrite indicated a coordination complex with dimethyl arsonic acid. The XPS results revealed that the Fe–O bonds on the surfaces of the magnetic ferrihydrite had coordination complexation effects on the As-O of the dimethyl arsonic acid.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Acids / Adsorption / Aquatic Pollution / Arsenic / Atmospheric Protection/Air Quality Control/Air Pollution / Bentonite / Bentonite - chemistry / Composite materials / Coordination compounds / Drinking water / Earth and Environmental Science / Ecotoxicology / Environment / Environmental Chemistry / Environmental Health / Environmental science / ferrihydrite / Ferrosoferric Oxide / Fourier transform infrared spectroscopy / Fourier transforms / Hydrogen-Ion Concentration / Infrared analysis / Infrared spectroscopy / Isotherms / Kinetics / Magnetic Phenomena / magnetism / Magnetite / Mathematical models / Photoelectron spectroscopy / Photoelectrons / pollutants / Research Article / Specific surface / Spectroscopy, Fourier Transform Infrared / Spectrum analysis / Surface area / Surface chemistry / Waste Water Technology / Water Management / Water Pollutants, Chemical - chemistry / Water Pollution Control / X ray photoelectron spectroscopy / Zeta potential