A Novel Magnetic Nano-Sorbent Functionalized from N-methyl-d-glucamine for Boron Removal from Desalinated Seawater

Abstract

Boron is a special pollutant. Because of its relatively small molecular weight, it can freely penetrate the reverse osmosis membrane in the same way that water molecules can in reverse osmosis during seawater desalination, which affects the effluent quality of desalinated seawater. In this study, a new magnetic adsorption material, MNP-NMDG, was synthesized by combining magnetic nanoparticles (MNPs) of Fe3O4 with N-methyl-d-glucamine with a high selectivity to boron, and MNP-NMDG was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The adsorption properties of the MNP-NMDG for boron during seawater desalination under static and dynamic conditions was studied from the aspects of pH, adsorbent dosage, adsorption kinetics, and isotherms. The results showed that according to the breakthrough curve of dynamic adsorption, MNP-NMDG had a high boron-adsorption capacity, and the static adsorption capacity was 9.21 mg/g. The adsorption performance was the best at pH = 9, and the adsorption equilibrium was achieved within 40 min. Boron adsorption conformed to the Freundlich adsorption isotherm and to the pseudo-second-order kinetic model. This composite material not only provides an effective and rapid way to remove boron from desalinated seawater, but also has a shorter removal time and makes it more easily separated using the external magnetic field.

Graphene oxide functionalized with N-methyl-d-glucamine as a novel sorbent for boron removal from produced and formation waters

“…18 Table 1 shows a comparison among different sorbent materials already employed for boron removal from aqueous medium. 19–27…”

“…18 Table 1 shows a comparison among different sorbent materials already employed for boron removal from aqueous medium. [19][20][21][22][23][24][25][26][27] In this study, a new material prepared by functionalizing GO with NMDG is proposed for boron removal in aqueous media. Graphene can be obtained as a 2-D nanomaterial with properties such as high surface area and relatively easy dispersion in water, 16,28,29 while GO can be obtained through mechanical exfoliation or chemical oxidation-reduction of graphite akes.…”