It is well known that water treatment of printing and dyeing wastewaters is problematic. In order to decompose dyes from dyestuff wastewater and convert them into almost harmless substances for the natural environment, an easily prepared, efficient, practical, and easy-to-regenerate composite material was produced from porous floating ceramsite loaded with cuprous oxide (PFCC). The PFCC samples were prepared and characterized by X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The material was applied for photocatalytic degradation of methyl orange (MO) in water. The results show that the maximal degradation rate of MO was 92.05% when the experimental conditions were as follows: cuprous oxide loading rate of 8%, PFCC dosage of 20 g/L, the reaction time of 2 h, pH value of 8, and solution initial concentration of 30 mg/L. The degradation processes of MO fits well with the Langmuir–Hinshelwood model in reaction kinetics, and the Freundlich model in reaction thermodynamics, respectively. The degradation mechanism of MO was considered from two perspectives—one was the synergetic effect of adsorption and photocatalytic oxidation, and the other was the strong oxidation of hydroxyl radicals produced by photocatalysts.

In this experiment, the influence of coal gangue as the admixture on the performance of dry-mixed mortar was studied, and the results were analyzed by XRD and SEM. The effects of different ways of crushing, particle size distribution, coal gangue, cement, admixture, and water content on the water retention, consistency, and 7 d compressive strength of dry-mixed mortar were investigated. The results show that the optimum content of hammer crushing of coal gangue through 3 mm sieve and cement is 83% and 17% of the total mass (W/W), respectively, the admixture content of 1# compound is 0.2 g/kg, and the amount of water is in the range of 194~200 mL/kg. At this time, the consistency can reach 91.5 mm, the water retention rate can reach 92.11%, and the 7 d compressive strength can reach 10.6 MPa, which meets the requirements of dry-mixed mortar for ordinary plastering and masonry mortar (GB-T 25181-2019).