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Excessive nitrogen (N) and phosphorus (P) result in serious eutrophication of water. In this study, magnesium modified acid bentonite was prepared by the impregnation method, and nitrogen and phosphorus were simultaneously removed by the magnesium ammonium phosphate method (MAP), which solved the problem of the poor adsorption capacity of bentonite. The morphology and structure of MgO-SBt were characterized by XRD, FT-IR, SEM, EDS, XPS, BET, etc. The results show that the acidified bentonite can increase the distance between bentonite layers, the layer spacing is expanded to 1.560 nm, and the specific surface area is expanded to 95.433 m 2 /g. After Mg modification, the characteristic peaks of MgO appear at 2θ of 42.95°, 62.31°, and 78.72°, indicating that MgO has been successfully loaded and that MgO bonded to the surface and interior pores of the acidified bentonite, boosting adsorption performance. When the dosage of MgO-SBt is 0.25 g/L, pH = 9, and N/P ratio is 5:1, the maximum adsorption capacity of MgO-SBt for N and P can reach 193.448 mg/g and 322.581 mg/g. In addition, the mechanism of the simultaneous adsorption of nitrogen and phosphorus by MgO-SBt was deeply characterized by the kinetic model, isothermal adsorption model, and thermodynamic model. The results showed that the simultaneous adsorption of nitrogen and phosphorus by MgO-SBt was chemisorption and a spontaneous exothermic process.

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In this study, zinc ferrate (ZnFe2O4) and polyaniline (PANI) were coated on the surface of FAC by hydrothermal and in situ polymerisation using the floating property of fly ash cenospheres (FAC) to form PANI‐ZnFe2O4/FAC composites. Compared with other reference materials, the PANI‐ZnFe2O4/FAC material not only solves the problem of less easy recycling, but also has significantly enhanced photocatalytic activity for methylene blue (MB). The significant increase in catalytic efficiency is attributed to the synergistic effect of PANI and ZnFe2O4 on the FAC surface resulting in efficient separation and low photogenerated charge complexation rates. In addition, cycling tests have shown the material to be stable and reusable. Active species capture experiments show that ⋅O2− and h+ play a dominant role in the reaction system.

As the environmental issues of organic dyes pollutants are becoming more and more severe, the need to develop emerging technologies to effectively eliminate pollutants is becoming increasingly urgent. In this work, the perovskite-type BaCeO3/Fe2O3 composites were successfully synthesized by a simple ultrasonic water bath. The obtained composite was characterized by various techniques such as XRD, FTIR, SEM and UV-Vis. The photocatalytic performance of the composite was investigated by degrading rhodamine B under 25 W and 254 nm UV irradiation. Moreover, we investigated the optimum preparation conditions of BaCeO3/Fe2O3 photocatalyst with a BaCeO3 to Fe2O3 mass ratio of 1:1 and a temperature of 50[Formula: see text]C for 2 h. In addition, the operating parameters of the photocatalytic reaction were systematically studied such as the initial concentration of solution, catalyst dosage and solution initial pH. The results showed that the photocatalytic decolorization rate of rhodamine B could reach 97.5% by adding 1 g/L BaCeO3/Fe2O3 photocatalyst to 100 mL of 20 mg/L rhodamine B solution at pH 2 for 2 h. What’s more, the BaCeO3/Fe2O3 catalyst was shown to be reusable and stable by cycling tests, and the use of active species trapping agents determined the predominance of [Formula: see text]O[Formula: see text] and h[Formula: see text] in the reaction system. Finally, the possible mechanism of enhancement of photocatalytic activity was initially discussed.

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