Effect of Pt impregnation on the textural properties, surface element distributions and catalytic behavior of a precipitated iron-based catalyst for FischerTropsch synthesis (FTS) was investigated by N 2 physical adsorption, temperature-programmed reduction (TPR), Mössbauer effect spectrometer (MES), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). Low levels of Pt addition lead to an increase in BET surface area. The result of XPS indicates that Pt enriches on the catalyst surface after being calcined. HRTEM shows that Pt crystallites with diameter about 2 nm are well dispersed on the surface of the catalyst (100Fe/1Pt/4 K/16SiO 2 ). The results of TPR and MES clearly indicate that Pt facilitates the reduction and carburization of Fe 2 O 3 to some extend. The reaction tests in a slurry reactor give the result that the Pt impregnation remarkably increases the FTS activity, and suppresses the selectivities of the light hydrocarbons and the olefins.

The activated carbon (AC) adsorption technology has been widely used in wastewater purification. Natural fiberbased AC is a group of emerging biomass adsorbents for dye adsorption; however, poor adsorption performance and a high preparation cost bring many limitations to its large-scale applications. Kapok fiber (KF) is a desirable and promising carbon source due to its low cost, renewability, unique hollow structure, and rich carbon content. Herein, novel KF-derived hierarchical porous biocarbons (KHPBs) were fabricated through a feasible two-step carbonization approach for the high-performance removal of cationic and anionic dyes from wastewater. The combined hollow structure and hierarchical pore structure of KHPBs greatly enlarged the adsorption capacity and removal rate of organic dyes. Due to their outstanding specific surface area (1455 m 2 /g) and pH responsiveness, the KHPBs possessed a large adsorption capacity of 1983.39 mg/g to Congo Red (CR). Moreover, the flexible KHPB filter element showed remarkable continuous filtration capacity to a cationic binary dye system, and the removal rate of it was almost 100% after 10 continuous filtrations. Therefore, the as-prepared KHPBs have a great application prospect as a highly efficient, economical, and eco-friendly adsorbent in organic dye wastewater purification.

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Large-area and flexible reduced graphene oxide (rGO)/Fe3O4 NPs/polyurethane (PU) composite films are fabricated by a facile solution-processable method. The monolayer assembly of Fe3O4 nanoparticles with a high particle-stacking density on the graphene oxide (GO) sheets is achieved by mixing two immiscible solutions of Fe3O4 nanoparticles in hexane and GO in dimethylformide (DMF) by a mild sonication. The x-ray diffraction and Raman spectrum confirm the reduced process of rGO by a simple thermal treatment. The permittivity value of the composite in a frequency range of 0.1 GHz–18 GHz increases with annealing temperature of GO increasing. For 5-wt% rGO/Fe3O4 NPs/PU, the maximum refection loss (RL) of over −35 dB appears at 4.5 GHz when the thickness of film increases to 5 mm. The rGO/Fe3O4 NPs/PU film, exhibiting good electromagnetic properties over GHz frequency range, could be a potential candidate as one of microwave absorption materials in flexible electronic devices.