Magnetic mesoporous silica hybrid nanoparticles for highly selective boron adsorption

Abstract

Novel core-shell magnetic mesoporous silica hybrid nanoparticles were synthesized and functionalized further with a glycidol reagent to produce boron-specific cis-diol, chelating functional derivatives. The resulting core-shell hybrid nanoparticles were found to be a better alternative to the existing boron adsorbents that had been modified with large molecular weight saccharide moieties and polymer functionalities. The magnetic mesoporous silica hybrid nanoparticles had a surface area, diameter, pore size, and saturation magnetization of 629 m 2 g À1 , 200-300 nm, 2.5 nm, and 33.25 emu g À1 , respectively. The glycidol-modified nanoparticles with cis-diol functional groups showed high adsorption affinity and excellent selectivity towards boron in an aqueous solution, even in the presence of competitive metal ions (Ni 2+ , Cu 2+ , Cr 2+ and Fe 2+ ) and sulphates and chlorides of Na + , K + , Ca 2+ and Mg 2+ ions. Adsorption equilibrium could be established within 15-20 min, and the level of boron adsorption was 2.37 mmol g À1 , which is much higher than the values previously reported for other boron adsorbent materials. The synthesized magnetic mesoporous silica hybrid nanoparticles showed approximately 97% boron removal capacity from a H 3 BO 3 solution (100 mg L À1 ), and the used adsorbent particles could be separated easily from the aqueous suspensions by an external magnetic field. The adsorbent could be used repeatedly after a simple acid treatment (0.1 M HCl) and regenerated by an aqueous ammonia solution (3% NH 3 $H 2 O).

Incorporation of N‐Methyl‐d‐glucamine Functionalized Oligomer into MIL‐101(Cr) for Highly Efficient Removal of Boric Acid from Water

“…The successful introduction of poly(Si‐NMDG) inside the cavities could be evident from FTIR spectra with the appearance of Si−O−Si stretching vibration characteristic band for the polymer at around 1057 cm −1 (Figure ) . All peaks of MIL‐101(Cr) can be correspondingly found in the spectrum of poly(Si‐NMDG)@MIL‐101(Cr).…”

Synthesis of magnetic molecular imprinted silica spheres for recognition of ciprofloxacin by metal-coordinate interaction

“…4). The peaks of MMIPs (b) at 2923 and 2853 cm -1 were attributed to the -CH 2 stretching vibration, the peaks at 3447 and 1630 cm -1 were due to the vibration of H 2 O, the absorbance peak at 1467 cm -1 was assigned to N-H vibration [21], the absorbance peak at 1083 cm -1 was due to Si-O-Si stretching vibration, and the band around 468 cm -1 was resulted from Si-O, which verified that amino-functioned silica spheres had been synthesized. The curves of MMIPs (b) and MNIPs (c) have the same characteristic peaks, indicating that they contain the same chemical composition.…”

Hollow Mesoporous Functional Hybrid Materials: Fascinating Platforms for Advanced Applications

“…In recent years, magnetic nanostructures have become a particularly important research field . Accordingly, several noteworthy magnetic hollow materials have also been reported because of their potential applications, such as drug delivery, adsorption of biomolecules, bioimaging, and pollutant adsorption . For example, titania‐coated magnetic HMS spheres (HMSSs) were produced for use in the efficient and rapid capture of phosphopeptides from peptide mixtures, while poly(isobutylene‐alt‐maleic anhydride)‐functionalized near‐infrared (NIR) IR‐820 dye and its conjugates with iron oxide (Fe 3 O 4 ) magnetic nanoparticles were designed for magnetic resonance imaging (MRI) applications …”

“…The magnetic mesoporous silica hybrid nanospheres were responsive to external stimuli, such as (i) UV‐light and (ii) pH‐triggered drug release. Core–shell magnetic mesoporous silica hybrid nanoparticles were also synthesized and functionalized further using a glycidol reagent to produce boron‐specific, cis‐diol, chelating functional derivatives …”