Bentonite/Magnetite Composite for Removal of Nitrofurazone

Abstract

The presence of pharmaceutical pollutants in the environment is one of the most pressing environmental problems. Adsorption from solution is an effective way to remove pharmaceuticals from liquid media, but the problem then is to separate the adsorbent from the liquids. The objective of the present study was to remove nitrofurazone from aqueous solutions using a bentonite/magnetite composite, prepared by co-precipitation of magnetite with bentonite, which could then be collected by magnetic separation. The bentonite/magnetite composite was characterized using diverse techniques, such as X-ray diffraction, scanning electron microscopy, low-temperature N2 adsorption/desorption, laser diffraction, and magnetization measurements. The particle size of the composite material did not exceed 50 μm and the particle size distribution was mono-modal with a maximum at 3.2 μm. The strong hysteresis in the magnetization curve revealed that the bentonite/magnetite particles were ferromagnetic. Adsorption of nitrofurazone by the bentonite/magnetite composite from aqueous solutions was measured and the amount of nitrofurazone adsorbed was 3.2×10–2 mmol/g. The adsorption kinetics of nitrofurazone to the bentonite/magnetite composite followed a pseudo-second-order kinetics equation. Upon adsorption, hydrogen bonds were formed between the amide groups of nitrofurazone and oxygen groups in bentonite.

Novel magnetic polymer/bentonite composite: Characterization and application for Re(VII) and W(VI) adsorption

“…The absorption band at 3740 cm -1 (Fig. 2a) is due to the stretching vibration of the free silanol groups [14]. The bands at 3350 cm -1 and 1650 cm -1 could be ascribed to the stretching and bending -OH vibrations of the water molecules adsorbed on the bentonite/magnetite surface.…”

“…The peak at 1400 cm -1 corresponds to the deformation vibrations of the -OH groups at the edges of the SiO 4 tetrahedra. A sharp band at 1045 cm -1 is attributed to the stretching vibrations of the Si-O-Si group [14,15]. The band at 400-700 cm −1 confirms the Fe-O bond [12], while the band at 466 cm −1 is attributed to the deformation vibrations of the Si-O-Si group [16].…”

Synthesis, structure and thermal properties of montmorillonite/ionic liquid ionogels

“…Recently, functional materials based on various clay minerals have been the subject of intensive research in connection with the possibility of their practical application in many industries, medicine, as well as for solving environmental problems. 1,2 Clay minerals are widely used in daily life due to their availability, low cost, unique texture and physicochemical properties, such as developed specic surface area, high adsorption and ion-exchange properties, thermal stability and the presence of active centers of various origins. One of the important clay minerals is montmorillonite (MMT).…”