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The mechanism of using graphene oxide as a two-dimensional filler to increase the path length of the corrosive medium to the metal surface is limited to improving the corrosion resistance of the coating. This study propose novel dispersion and in-situ crosslinking reaction mechanism for constructing water-based heavy-duty anticorrosive coatings by using graphene oxide (GO) and waterborne epoxy resin (WEP). The results showed that GO can be uniformly dispersed directly into WEP without complex functional modifications. Oxygen-containing functional groups on moleculars structure of GO&WEP co-polymerized with diethylenetriamine (DETA) forming a continuous phase film which improved the density of the coating. Characterization techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal conductivity measurement instrument, pencil hardness tester, adhesion tester, salt spray corrosion test chamber, and electrochemical impedance spectroscopy (EIS) were used to evaluate coating structure and performance properties. The results showed that graphene characteristics enhanced physical properties and anti-corrosion performance of composite coatings. The construction mechanism of the coating is different from that of the current GO modified and dispersed in the coating as a two-dimensional filler to extend the path length of the corrosive medium to the metal surface. The coatings prepared by adding the optimum mass ratio of 0.1–0.2 % GO to WEP have the best physical properties and anti-corrosion properties. When the GO content is 0.2 wt%, the thermal conductivity increases by 86.0 %. After added 0.025 wt% GO, the coating hardness is increased by two grades directly from 2B to HB. With the addition of GO concentration increased to 0.05 wt%, the adhesion is increased from 2 to level 1.When the GO content exceeds 0.05 %, the coating will not bulge off after 4 months of salt water immersion experiment.

As a bulk industrial solid waste, coal gangue has caused serious pollution to the environment, and its application in the field of soil amendments has been widely studied, but the mechanism of pore structure regulation of coal gangue as soil substrate has not been reported in the literature. In this paper, the physical and chemical properties of coal gangue are analyzed, and its particle size, element content, and occurrence state are defined. The regulation mechanism of pores and pores in preparing matrix soil with coal gangue is revealed, and an efficient and energy-saving fluidizing activation technology is proposed to prepare active matrix soil. The results show that matrix soil with optimal pore structure can be obtained by fluidized bed calcination at 700 °C for 15 min, with a porosity of 55.0 %, volumetric water content of 28.7 %, and gas phase rate of 24.8 %. The technology also removes carbon, which is prone to natural fires, and fixes sulfur, which is good for plant growth. The formation and regulation mechanism of pores structure of soil matrix prepared by fluidized calcination of coal gangue is as follows: The oxidation reaction of carbon and the decomposition of minerals in coal gangue will form pore structures. Adjusting the reaction temperature and time, controlling the rate of carbon oxidation reaction, and the rate of mineral decomposition can achieve the goal of regulating the pore structure. Large pores with a pore size greater than 0.03 mm are formed by the oxidation of carbon and the decomposition of kaolinite. The pores with a diameter of 0.0001–0.03 mm are formed by the overflow of carbon dioxide gas, which is generated by the oxidation reaction of carbon embedded in coal gangue particles and the decomposition of calcium carbonate. The results of this study will provide technical and theoretical support for promoting the comprehensive utilization of coal gangue and improving environmental protection.

The key step of the control reaction for the preparation of graphene oxide (GO) by chemical oxidation of KMnO4/ concentrated H2SO4 oxidation system is the intercalation mass transfer process of oxidizer in graphite. Ultrasonic field can promote the intercalation mass transfer process, but the mass transfer kinetics remains unclear. In this paper, the kinetic model of mass transfer coefficient of graphene oxide sheet intercalated by Mn2O7 oxidizer in ultrasonic field was established. The Mn2O7 intercalation process after the intervention of the ultrasonic was simulated by COMSOL Multiphysics 5.5 simulation software. The results show that the ultrasonic field makes the Mn2O7 solution inside and outside the graphite layer turbulent, and the ultrasonic intervening time has little influence on the concentration distribution and diffusion rate of the solution outside the graphite layer, while it has great influence on the concentration distribution and little influence on the diffusion rate change inside the graphite layer. These results contribute to the improvement of the mass transfer theory for the preparation of GO by ultrasonic assisted chemical oxidation.