Fe₃O₄@C Core–Shell Carbon Hybrid Materials as Magnetically Separable Adsorbents for the Removal of Dibenzothiophene in Fuels

Abstract

Herein, we demonstrate a new class of core–shell magnetic carbon hybrid materials (Fe 3 O 4 @C) for remarkable adsorptive desulfurization of dibenzothiophene (DBT), which have been successfully prepared through hydrocarbonization of glucose on the surface of Fe 3 O 4 and the subsequent pyrolyzation process. The as-obtained Fe 3 O 4 @C retains amorphous nature of carbon shells with a large surface area and displays an increase of iron atoms as active sites under elevated pyrolyzation temperature which is favorable in the adsorption of sulfur-containing species through physical and chemical adsorption, respectively. We investigate the adsorption capacity and efficiency of Fe 3 O 4 @C as a magnetically adsorbent for the removal of DBT in model oils under various experimental conditions including the adsorbent obtained at different temperatures, the amount of adsorbents, the DBT initial concentration, the regeneration approach, as well as the interference species. Our results demonstrated that the as-obtained Fe 3 O 4 @C at 650 °C (Fe 3 O 4 @C-650) displays a remarkable estimated adsorption performance (57.5 mg DBT/g for 200 ppmw), extraordinary high desulfurization efficiency (99% for 200 ppmw), and a high selectivity for DBT compared with its derivatives. Moreover, Fe 3 O 4 @C can be recovered in a quite easy, economical, and eco-friendly manner by an external magnet after five cycles without significant weight loss, which significantly simplifies the operation procedure and favors the recycle of Fe 3 O 4 @C. Combined with the economic and eco-friendly merits, Fe 3 O 4 @C offers a new avenue to employ the magnetic carbon materials for industrial applications and provides a promising substitute for adsorptive desulfurization in view of academic, industrial, and environmental aspects.

Fe3O4-Based Melamine-Rich Covalent Organic Polymer for Simultaneous Removal of Auramine O and Rhodamine B

“…MO nanostructures are especially of interest because of their promising features. , Among these, iron oxide nanoparticles (Fe 3 O 4 NPs) are of huge emphasis, owing to their easy production, cost-effectiveness, and extraordinary magnetic permeability. , Nevertheless, applications of these NPs are restricted by their easy aggregation due to high surface free energy, specific surface area, and straightforward oxidation, and they also create a pressure drop in the adsorption process . To overcome these difficulties, a variety of modification approaches were attempted by adding different compounds to enhance the dispersibility and stability of Fe 3 O 4 NPs. , So far, diverse materials have been effectively utilized to modify Fe 3 O 4 NPs, including different organic and inorganic modifiers that can be termed as cyclodextrins, silanes, MOFs, , and COFs .…”

“…COP is similar to COFs and is an attractive class of highly porous organic material that has attracted substantial attention in adsorption and separation, catalysis, sensing, proton conductivity, and drug delivery owing to its high porosity, extraordinary surface area, good thermal stability, and topologically designable structures. , COPs have been well-known as an appealing alternative to MOFs as they offer more stability to various environments. They are generated through covalent bond construction reactions, and functional moieties such as imine, triazole, and hydrazine could be easily incorporated into COPs during their fabrication processes …”

“…20,29 Among these, iron oxide nanoparticles (Fe 3 O 4 NPs) are of huge emphasis, owing to their easy production, cost-effectiveness, and extraordinary magnetic permeability. 30,31 Nevertheless, applications of these NPs are restricted by their easy aggregation due to high surface free energy, specific surface area, and straightforward oxidation, and they also create a pressure drop in the adsorption process. 32 To overcome these difficulties, a variety of modification approaches were attempted by adding different compounds to enhance the dispersibility and stability of Fe 3 O 4 NPs.…”

“…They are generated through covalent bond construction reactions, and functional moieties such as imine, triazole, and hydrazine could be easily incorporated into COPs during their fabrication processes. 30 Herein, we represent in situ growth of melamine-rich COP generated from benzene-1,4-dicarboxaldehyde and melamine via the Schiff-base production of Fe 3 O 4 NP cross-linking using glucose and polyacrylonitrile. The prepared Fe 3 O 4 /C−COP was employed as a hopeful adsorbent for the successful simultaneous removal of AO and RB under ultrasound waves.…”

Enhancement of Photocatalytic Activity under Visible Light Irradiation via the AgI@TCNQ Core-Shell Structure

“…The core-shell structure has obvious advantages in terms of increasing the contact area between materials due to its unique face-to-face cladding structure; accordingly, the photo-generated charge could be transferred quickly between the semiconductor materials [11,12]. Meanwhile, the shell material could also protect the core particles to some extent and prevent its direct contact with the external environment [13].…”