g-C3N4-Based Photocatalytic Materials for Converting CO2 Into Energy: A Review.

Environmental pollution management and renewable energy development are humanity's biggest issues in the 21st century. The rise in atmospheric CO2, which has surpassed 400 parts per million, has stimulated research on CO2 reduction and conversion methods. Presently, photocatalytic conversion of CO2 to valuable hydrocarbons enables the transformation of solar energy into chemical energy and offers a novel avenue for energy conversion while regulating the greenhouse effect. This is an ideal strategy for simultaneously addressing environmental issues and the energy crisis. Photocatalysts are essential to photocatalytic processes. Photocatalyst is the core of photocatalytic technology, and graphite carbon nitride (g-C3N4) has attracted much attention because of its nonmetallic characteristics, and it has the characteristics of low cost, tunable electronic structure, easy manufacture and strong reducibility. However, its activity is not only affected by external reaction conditions, but also by the band gap structure, physical and chemical stability, surface morphology and specific surface area of the photocatalyst it. In this paper, the application progress of g-C3N4-based photocatalytic materials in CO2 reduction is reviewed, and the modification strategies of g-C3N4-based catalysts to obtain better catalytic efficiency and selectivity in CO2 photocatalytic reduction are summarized, and the future development of this material is prospected.

Study on the Performance Test of Fe-Ce-Al/MMT Catalysts with Different Fe/Ce Molar Ratios for Coking Wastewater Treatment.

It is very important to choose a suitable method and catalyst to treat coking wastewater. In this study, Fe-Ce-Al/MMT catalysts with different Fe/Ce molar ratios were prepared, characterized by XRD, SEM, and N2 adsorption/desorption, and treated with coking wastewater. The results showed that the optimal Fe-Ce-Al/MMT catalyst with a molar ratio of Fe/Ce of 7/3 has larger interlayer spacing, specific surface area, and pore volume. Based on the composition analysis of real coking wastewater and the study of phenol simulated wastewater, the response surface test of the best catalyst for real coking wastewater was carried out, and the results are as follows: initial pH 3.46, H2O2 dosage 19.02 mL/L, Fe2+ dosage 5475.39 mL/L, reaction temperature 60 °C, and reaction time 248.14 min. Under these conditions, the COD removal rate was 86.23%.