•ESM-derived MgFe2O4 was prepared and characterized.•ESM-derived MgFe2O4 showed high adsorption capacity of 308 mg g−1 for doxycycline in aqueous solution.•Adsorption kinetics and adsorption isotherm were investigated.•ESM-derived MgFe2O4 could be reused after magnetic separation from water and acid treatment.•Doxycycline strongly adsorbs on ESM-derived MgFe2O4 via hydrogen bonding and π–π stacking interaction.Here, we report eggshell membrane (ESM)-derived MgFe2O4 as effective adsorbent for the capture, transfer, and removal of doxycycline (DC) antibiotic and its subsequent recycling for cyclic utilization. The resultant material has meshwork morphology and consists of interconnected and penetrated fibers assembled by MgFe2O4 nanoparticles. The maximal adsorption capacity of ESM-derived MgFe2O4 is about 308 mg g−1 for DC, and the adsorbed MgFe2O4 can be reused after magnetic separation from water and acid treatment. The strong adsorption ability is attributed to the hydrogen bonding and π–π stacking interaction between ESM-derived MgFe2O4 and DC, as well as its porous structure with high surface area.Download high-res image (213KB)Download full-size image

Hierarchically porous ZnAl-LDH/ZnCo2O4 composites were synthesized by pine pollen via a two-step process involving self-assembly of ZnCo2O4 nanoparticles and hydrothermal synthesis of zinc aluminum layered double hydroxide with CO32− as interlayer anion (abbreviated as ZnAl-LDH). The characteristics of the obtained samples were investigated by XRD, SEM, EDS, TEM, FTIR, BET and DRS. These results demonstrated that the synthesized ZnAl-LDH/ZnCo2O4 and its derived metal oxides all retained the structure of pine pollen grains. Layered ZnAl-LDH was dispersed uniformly on the surface of a support of ZnCo2O4 ellipsoids. The adsorption of Congo red (CR) onto the as-synthesized samples was systematically investigated. The kinetic studies suggested that the adsorption process followed a pseudo-second-order kinetic model. In addition, the catalytic activities of the obtained samples for CR degradation under simulative sunlight irradiation were also evaluated. It was found that the derived metal oxides exhibited better catalytic activity for CR degradation than ZnAl-LDH/ZnCo2O4 and the degrading efficiency of CR was about 91%.

•A new biomass route for the synthesis of SnO2/ACF hybrid catalyst was proposed.•The original fibrous structure of kapok fiber was retained in the SnO2/ACF hybrid catalyst.•SnO2/ACF hybrid catalyst exhibited high BET surface area (647–897 m2/g) and large pore volume (0.36–0.56 cm3 g−1).•High microwave-induced catalytic activity for methyl violet degradation was obtained.SnO2/activated carbon fiber (ACF) hybrid catalyst was synthesized from kapok precursor via a two-step process involving pore-fabricating and self-assembly of SnO2 nanoparticles. The morphology and phase structure of the obtained samples were characterized by X-ray diffraction, field emission scanning electron microscope, high resolution transmission electron microscopy and N2 adsorption-desorption isotherm. These results demonstrated that the synthesized SnO2/ACF retained the hollow-fiber structure of kapok fibers. SnO2 nanoparticles dispersed uniformly over the ACF support. The obtained hybrid catalyst showed porous structure with high surface area (647–897 m2/g) and large pore volume (0.36–0.56 cm3 g−1). In addition, the catalytic activities of the obtained samples for methyl violet degradation under microwave irradiation were also evaluated. It was found that the SnO2/ACF catalyst exhibited high catalytic activity for methyl violet degradation due to the synergistic effect of microwave and SnO2/ACF catalyst.

Near fully dense Fe3Al(10Ti)/TiC composites were synthesized by MA and hot-pressing sintering methods. Based on the Orowan strengthening effect offered by the nano-TiC particles, higher three-point bending strength and hardness values, 1310 MPa and 90 HRA, were achieved in Fe3Al(10Ti)/40 vol%TiC composite. The addition of Ti favored the improvement of hardness and room temperature bending strength of composites by the ordering strengthening effect and solid solution hardening effect. The microstructures of as-synthesized composites were investigated by XRD, SEM and TEM. Fe3Al particles had equiaxed morphology. TiC particles with grain size ranging from 50 to 200 nm were homogeneously dispersed in Fe3Al matrix. The larger TiC particles with sub-micrometer were mainly located at grain boundaries and the smaller ones were within matrix grains.

Hierarchically porous Fe3O4@MgAl–LDH magnetic microspheres were reported as novel efficient adsorbent for the removal of anionic dye from water. The as-prepared microspheres had vertically/slantly/horizontally oriented platelets-coated morphology, and exhibited superb adsorption capacity of 813.0 mg/g for Congo red (CR), which was the highest reported value of magnetic adsorbents. The adsorption kinetics and isotherm of CR on microspheres followed the pseudo-second-order and Langmuir model, respectively, and the adsorption processes were spontaneous and endothermic in nature. The adsorbed samples could be regenerated by methanol, and easily magnetically separated from aqueous solution. The synthesized materials might act as excellent adsorbents for environmental processes.Download high-res image (70KB)Download full-size image