High-temperature hydrothermal synthesis of magnetically active, ordered mesoporous resin and carbon monoliths with reusable adsorption for organic dye

Preparation of magnetic mesoporous metal-phenolic coordination spheres for extraction of crystal violet and leuco-metabolites in fish

To address the undesirably low porosity of phenolic resin, a new material termed magnetic mesoporous metal-phenolic coordination spheres (Fe₃O₄@Co-TA) was synthesized by chelating tannic acid (TA) with metal ions. Fe₃O₄@Co-TA was characterized by transmission electron microscopy, scanning electron microscopy, hysteresis loop (B-H) analysis, Fourier-transform infrared spectroscopy, and N₂ adsorption-desorption. The results indicated that the new material comprises mesopores (2 nm and 3 nm) and exhibits a good magnetic response (44 emu/g). Combined with high-performance liquid chromatography (HPLC), a novel method for the detection of crystal violet (CV) and leucocrystal violet (LCV) by magnetic solid-phase extraction was established. Under the optimal extraction conditions, the linear ranges of CV and LCV detection were 0.2‒60 μg/L and 0.04‒40 μg/L, the detection limits were 0.04 μg/L and 0.008 μg/L, and the enrichment factors were 435 and 460, respectively. Fe₃O₄@Co-TA was reused ten times without significant reduction of the extraction ability. This method was successfully used for the detection of CV and LCV in fish samples, providing an effective technique for food safety monitoring and quality control.

Adsorptive removal of Rhodamine B from aqueous solution by nanoporous polydivinylbenzene

Nanoporous polydivinylbenzene (PDVB) material has been successfully prepared via the copolymerization of divinylbenzene monomers. The nanoporous PDVB was characterized through N₂ adsorption/desorption isotherms, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The nanoporous PDVB as an adsorbent was applied for the removal of Rhodamine B (RhB). The adsorption behavior of PDVB for the removal of RhB showed that the isotherm data followed the Langmuir isotherm model and the kinetic adsorption obeyed the pseudo-second-order model. Thermodynamic parameters illustrated that the adsorption process was spontaneous and exothermic. Interestingly, the spent nanoporous PDVB has excellent regenerative performance through treating it with ethanol. These results revealed that PDVB might be an excellent adsorbent for the removal of RhB from wastewater.

Porosity control in mesoporous polymers using CO2-swollen block copolymer micelles as templates and their use as catalyst supports

Mesoporous polymers with tunable large mesopores (14–22 nm) were synthesized through a CO₂-swollen micelle templating route.