A high-performance MnFe2O4@ZIF-8 magnetic composite was successfully designed and synthesized, and its adsorption behavior toward doxycycline (DOX) was systematically investigated. Structural characterization by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) confirmed the effective incorporation of MnFe2O4 nanoparticles into the ZIF-8 framework, while magnetic hysteresis measurements demonstrated favorable magnetic responsiveness, enabling rapid separation under an external magnetic field. Adsorption equilibrium data were well described by the Langmuir isotherm model, which yielded a model-derived maximum monolayer adsorption capacity (qm) of 3235.5 mg/g at 25 degrees C. Kinetic, thermodynamic, and adsorption behavior analyses indicated that the adsorption process was spontaneous and endothermic. Based on the combined results of FT-IR spectroscopy, zeta potential analysis, pH-dependent adsorption experiments, and adsorption studies, the adsorption of DOX onto MnFe2O4@ZIF-8 is proposed to involve multiple cooperative interactions, including electrostatic attraction, hydrogen bonding, pi-pi interactions, possible metal-DOX coordination, and pore-filling/spatial confinement effects. In addition, the composite maintained good adsorption performance after four consecutive adsorption-desorption cycles, demonstrating promising recyclability. The results suggest that MnFe2O4@ZIF-8 is a promising magnetic adsorbent for the removal of antibiotic contaminants from aqueous environments and provide useful insights for the design of multifunctional MOF-based adsorbents for water treatment applications.
Valorizing agricultural residues such as palm waste in construction materials offers a promising route toward more sustainable fired clay bricks production. This study investigates the effects of incorporating 2, 4 and6 wt
This study presents the fabrication and characterization of titanium (Ti) foams using ceramic polishing waste (CPW) as a reactive pore-forming additive through the Electric Current Assisted Sintering (ECAS) method. CPW obtained from a ceramic factory in Turkey were blended in varying proportions (10–80 wt
The methyl groups on the surface of hydrophobic aerogels make them moisture-resistant and weather-resistant, ensuring their structural integrity. However, many scholars have realized that the surface methyl groups of aerogels can also pose fire safety issues under strong thermal radiation. In this work, a flame-retardant hydrophobic aerogel was prepared by in-situ chemical grafting, and the ammonium dihydrogen phosphate group was grafted into the SiO2 polymer network through chemical bonds from 3-aminopropyltriethoxysilane (APTES). The cone calorimeter test showed that the heat release rate, peak heat release rate and total heat release rate of hydrophobic silica aerogel modified with flame-retardant groups are significantly lower than those of pure hydrophobic silica aerogels. The ignition time (TTI) of aerogel with APTES was significantly prolonged, reaching to 9 10s (vs. 7s for pure aerogels). Synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) was used to finely analyze the flame-retardant mechanism of aerogels modified with flame-retardant groups. The results showed that pure aerogels had a maximum CO generation rate peak at around 490 °C, while aerogels modified with flame-retardant groups had two maximum CO generation rate peaks. The first was similar to the former, and the latter was around 647 °C. Because flame-retardant groups was connected to the pyrolysis of the amino group in the aerogel, the generated ammonia gas inhibited the pyrolysis of the methyl group, which delayed the CO generation peak and slowed down the generation of combustible gas, thereby effectively improving the performance of flame retardancy of the aerogels. TG-DSC analysis could also obtain similar results. As the content of APTES increased, the heat of pyrolysis decreased by up to 32.5 J/g, which showed that the introduction of amino groups reduced the heat release of the aerogel during the pyrolysis process, which was beneficial to reduce thermal hazards of hydrophobic silica aerogels.
Selective catalytic reduction of NOx with NH3 (NH3-SCR) constitutes the cornerstone of diesel and stationary emission control, yet reconciling robust low-temperature activity with high N2 selectivity remains an unresolved challenge. We report a seed-assisted hydrothermal route in which copper-sequestered seeds are incorporated directly into the ZSM-5 crystallization gel, enabling simultaneous framework growth and controlled Cu2+ anchoring. Three Cu-ZSM-5 catalysts (S1–S3, 0.6–1.7wt
