Preparation and Characterization of Magnetic Porous Carbon Microspheres for Removal of Methylene Blue by a Heterogeneous Fenton Reaction

Abstract

High-specific-surface-area magnetic porous carbon microspheres (MPCMSs) were fabricated by annealing Fe(2+)-treated porous polystyrene (PS) microspheres, which were prepared using a two-step seed emulsion polymerization process. The resulting porous microspheres were then sulfonated, and Fe(2+) was loaded by ion exchange, followed by annealing at 250 °C for 1 h under an ambient atmosphere to obtain the PS-250 composite. The MPCMS-500 and MPCMS-800 composites were obtained by annealing PS-250 at 500 and 800 °C for 1 h, respectively. The iron oxide in MPCMS-500 mainly existed in the form of Fe3O4, which was concluded by characterization. The MPCMS-500 carbon microspheres were used as catalysts in heterogeneous Fenton reactions to remove methylene blue (MB) from wastewater with the help of H2O2 and NH2OH. The results indicated that this catalytic system has a good performance in terms of removal of MB; it could remove 40 mg L(-1) of MB within 40 min. After the reaction, the catalyst was conveniently separated from the media within several seconds using an external magnetic field, and the catalytic activity was still viable even after 10 removal cycles. The good catalytic performance of the composites could be attributed to synergy between the functions of the porous carbon support and the Fe3O4 nanoparticles embedded in the carrier. This work indicates that porous carbon spheres provide good support for the development of a highly efficient heterogeneous Fenton catalyst useful for environmental pollution cleanup.

A facile approach to the fabrication of rattle-type magnetic carbon nanospheres for removal of methylene blue in water

“…6), the relatively strong reflection peaks at 2h = 30.0°, 35.5°, 43.2°, 53.8°, 57.2°, and 62.6°were ascribed to the (2 2 0), (3 1 1), (4 0 0), (4 2 2), (5 1 1), and (4 4 0) planes, which was in good agreement with the database of magnetite (JCPDS 65-3107). These data indicated that the Fe 3 O 4 had been successfully coated with SiO 2 and RF shells, resulting in a highly crystalline cubic spinel structure [37,38]. In Fig.…”

“…It also produces iron sludge as a byproduct of the treatment, which is an additional environmental contaminant [62]. Fe 3 O 4 nanospheres are an ideal heterogeneous Fenton catalyst due to the existence of Fe 2+ [38,63,64]. This material is free from some of the disadvantages of homogeneity mentioned above, and its magnetic capabilities offer the additional advantage of making it easier to separate from the reaction mixture via an external magnetic field.…”

Hydrothermal Treatment of Tannin: A Route to Porous Metal Oxides and Metal/Carbon Hybrid Materials

“…Magnetic porous carbons have been already prepared and suggested for a number of adsorption applications in the liquid phase [61][62][63]. Iron-containing activated carbons can indeed be more easily recovered out of the effluents after some targeted pollutants are removed.…”

Magnetic properties of NiO (nickel oxide) nanoparticles: Blocking temperature and Neel temperature

“…are very interesting for the investigation of magnetic properties and applications [27,[58][59][60].…”