Considering disadvantages such as the low thermal stability and environmental pollution of existing gel inhibitors, a green and stable intumescent nanoinhibitor (INI) was prepared and tested. First, polyacrylamide (PAM), nano-silica, and intumescent flame retardant (IFR) were selected as raw materials. The INI was prepared by nanoparticle modification and cross-linking polymerization. Then, the structure and physical properties of INI were tested by Fourier transform infrared spectroscopy, scanning electron microscopy, and rheological experiments. Meanwhile, the inhibition performance of INI was studied through thermogravimetric analysis-Fourier transfer infrared spectroscopy (TGA-FTIR) analysis. The results suggest that the nanomodification improved the dispersibility of INI particles. The addition of modified nano-silica (MNS) and IFR enhances the strength of the reticular structure, thereby improving the transport convenience and covering ability of the INI gel. At high temperatures, IFR can generate a porous foamed carbon layer that further coats the coal. After INI inhibition treatment, the characteristic temperature and activation energy of coal were significantly improved, and the production of carbon monoxide and carbon dioxide decreased. Hence, irrespective of physical properties, physical inhibition performance, or chemical inhibition performance, INI performed well. Research results can provide valuable references for the preparation and performance study of a coal spontaneous combustion inhibitor.

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Mine road dust is an important source of dust in mine operations. The dust produced on the road surface is a great hazard to the workers. Aiming at the road dust of an open-pit mine, this paper conducts physical and chemical analysis of a dust suppressant prepared by using sodium polyacrylate as a binder, sodium carbonate as a moisture absorbent, polyethylene glycol as a water-retaining agent, and alkyl glycoside as a surfactant. Characterization of characteristics and dust suppression performance. The results show that the dust suppressant has a pH of 11.03, a viscosity of 18.5 mPa·s, and a surface tension of 28.1 mN/m. The content of heavy metal ions contained is less than the maximum concentration defined by the national standard. Under the same temperature condition, the greater the humidity, the stronger the hygroscopicity, especially when the humidity is 30%, where the better hygroscopic effect than water is obvious. The dust suppressant also has good anti-evaporation properties and it keeps at 4–5% moisture content after 10 days at a normal temperature. Compared with water, the dust suppressant has better resistance to wind erosion and compression. Under the same conditions, the loss rate of water is 2 times that of the dust suppressant and the pressure of the dust suppressant sample is about 3 times that of water. The dust suppressant has a much higher dust removal efficiency for all dust and respirable dust than water under the same conditions. Finally, the test results and mechanism of the dust suppression effect of the dust suppressant are described and analyzed, which shows that the dust suppressant studied in this paper has good performance and is suitable for road dust prevention.

Conversion of methane into high value added chemicals and clean fuels such as methanol under mild conditions is of great importance to the chemical industry. However, traditional thermal catalytic of methane always suffer from harsh reaction conditions and poor product selectivity. Here, we reported photoelectrocatalytic oxidation of methane over BiVO4/Au/FeCo–LDH under simulated sunlight illumination with ambient‘ conditions. The results demonstrate that BiVO4/Au/FeCo–LDH exhibits excellent photoelectrochemical properties and catalytic activity. The double-layer capacitance ([Formula: see text]) value of BiVO4/Au/FeCo–LDH is estimated to be 3.00[Formula: see text]mF[Formula: see text]cm[Formula: see text], indicating its considerable electrochemical active areas. The photocurrent density of BiVO4/Au/FeCo–LDH reaches up to 1.46[Formula: see text]mA[Formula: see text]cm[Formula: see text] in methane atmosphere. The methanol yield for photoelectrocatalytic oxidation of methane is 8.46 times that of pure BiVO4, and the corresponding Faraday efficiency is 56.09%. Finally, the reaction mechanism of photoelectrocatalytic conversion of methane to methanol based on hydroxyl radical and methyl radical as intermediate products is proposed. Our finding is expected to provide new insight for the design of active and selective catalysts toward photoelectrocatalytic conversion of methane.