Fabrication of superparamagnetic adsorbent based on layered double hydroxide as effective nanoadsorbent for removal of Sb (III) from water samples.

In this study, the superparamagnetic adsorbent as Fe@Mg-Al LDH was synthesised by different methods with two steps for the removal of heavy metal ions from water samples. An easy, practical, economical, and replicable method was introduced to remove water contaminants, including heavy ions from aquatic environments. Moreover, the structure of superparamagnetic adsorbent was investigated by various methods including Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and vibrating sample magnetometer. For better separation, ethylenediaminetetraacetic acid ligand was used, forming a complex with antimony ions to create suitable conditions for the removal of these ions. Cadmium and antimony ions were studied by floatation in aqueous environments with this superparamagnetic adsorbent owing to effective factors such as pH, amount of superparamagnetic adsorbent, contact time, sample temperature, volume, and ligand concentration. The model of Freundlich, Langmuir, and Temkin isotherms was studied to qualitatively evaluate the adsorption of antimony ions by the superparamagnetic adsorbent. The value of loaded antimony metal ions with Fe@Mg-Al LDH was resulted at 160.15 mg/g. The standard deviation value in this procedure was found at 7.92%. The desorption volume of antimony metal ions by the adsorbent was found to be 25 ml. The thermodynamic parameters as well as the effect of interfering ions were investigated by graphite furnace atomic absorption spectrometry.

Magnetic nanobiosorbent (MG-Chi/Fe3 O4 ) for dispersive solid-phase extraction of Cu(II), Pb(II), and Cd(II) followed by flame atomic absorption spectrometry determination.

Trace amounts of Cu (II), Pb (II), and Cd (II) in a wastewater sample were preconcentrated with a novel cross-linked magnetic chitosan modified with a new synthesised methionine-glutaraldehyde Schiff's base (MG-Chi/Fe3 O4 ) as a dispersive solid-phase extraction (DSPE) adsorbent. The adsorbed metal ions were then eluted with a specific volume of suitable solution and determined by flame atomic absorption spectrometry (FAAS). Various parameters affecting the extraction efficiency of the metal ions were investigated and optimised, including pH, amount of adsorbent, extraction time, type and volume rate of eluent, elution time, sample volume, and effect of interfering ions. The adsorption kinetics are more consistent with the pseudo-second order model. The results were statistically interpreted and the analytical performance of the proposed method was found to have preconcentration factors of 55, 60, and 50 µg L-1 for Cu(II), Pb(II), and Cd(II), respectively, limits of detection were 0.22, 0.24, and 0.10 µg L-1 for Cu(II), Pb(II), and Cd(II), respectively, with a relative standard deviation (1.5%-2.8 %), and the liner range was 5-1000 for Cu(II) and Pb(II) and 2.5-1000 for Cd(II). It was concluded that this method was suitable for successful simultaneous determination of Cu(II), Pb(II), and Cd(II) in industrial wastewater samples.