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ZSM-5 has been regarded as one of the potential materials for separating substances from the mixture; however, their micropore channel is not favorable to load new active sites and adsorbate species. Herein, the pseudomorphic transformation method was used to convert high-aluminum-content micropore ZSM-5 into mesoporous structure (ZSM-5K). The samples of ZSM-5 and ZSM-5K were modified by Ce2(SO4)3 via the same impregnation route, and the obtained samples were used to adsorb As(V) from aqueous solution. The As(V) removal percentage and the X-ray diffraction data indicate that Ce2(SO4)3 was the effective adsorption site due to the high affinity between As(V) species and Ce. The N2 adsorption–desorption isotherms show that the linear connection between As(V) removal and BET surface of adsorbents was been obtained. The transmission electron microscopy results showed that mesoporous structure was more favorable to disperse the adsorption sites. In addition, the As(V) equilibrium adsorption data were fitted well by the Langmuir isotherm, and the maximum adsorption capacity was found as 31.63 mg/g, which was larger than that of the conventional alumina, carbon, iron oxide, etc. The adsorption kinetics under different initial concentration obeyed the pseudo-second-order model.

A new liquid polyborosilazane precursor for Si–B–C–N ceramic was synthesized by co-condensation reaction of boron trichloride, organodichlorosilanes, and hexamethyldisilazane. The structure and properties of polyborosilazane were studied by means of Fourier transform-infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), rheology, and thermogravimetric analysis (TGA). The conversion of polymer to ceramic and the high-temperature behavior of the new polymer-derived ceramic were investigated by TG–MS, FT-IR, X-ray diffraction (XRD) and high-temperature TGA (HTGA). The ceramics showed good oxidative resistance and thermal stability with weight gain of 1.8 wt% at 1350 °C under air atmosphere and weight loss of 2.6% at 1900 °C under Ar atmosphere.

Two-phase composites consisting of (1 − x) Al2O3 and xTi3SiC2 (x = 0−1) were prepared by spark plasma sintering (SPS). Sintered densities larger than 98% of theoretical density were achieved when the specimens were sintered at 1300°C for 5 min (in vacuum, at pressure 30 MPa). When content of Ti3SiC2 increased up to 30 wt%, composites were found to be machinable—they could be drilled easily using conventional Fe-Mo-W drills or gravers. The mechanical properties of the (1 − x) Al2O3−xTi3SiC2 composites were evaluated. The bending strength, Vickers hardness of the specimens had the following ranges: 428 ± 10.2 (x = 0) to 673 ± 15.4 Mpa (x = 1) (bending strength at room temperature); 19.9 (x = 0) to 4.0 GPa (x = 1) (Vickers hardness).