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The coal seam group in the outburst mine has the characteristics of mutual influence in the mining process, the goaf is connected, there are many air leakage places, and the fire prevention work is difficult. In order to accurately predict the coal spontaneous combustion process of the coal seam group near outburst mines, taking Guizhou Fa’er Coal Mine as an example, the variation law of each gas during the coal oxidation process was analyzed through the coal spontaneous combustion temperature programmed experiment, the comprehensive prediction indicators of the coal self -combustion single index gas and the marked gas ratio were determined, and the coal spontaneous combustion monitoring and early warning system and the field layout were proposed. The results show that the critical temperature range of each coal seam in Fa’er Coal Mine is 70-80 ℃, and the dry cracking temperature range is 130-140 ℃. Combined with the oxygen consumption, the occurrence temperature and change law of CO and C2H4, the priority order of spontaneous combustion oxidation of different coal seams in Fa’er Coal Mine is: 1# coal>3# coal>5-2# coal>5-3# coal>10# coal>7# coal. According to the experimental results and field data, six gas indexes(CO, O2, C2H4, ?渍(CO)/?渍(CO2), ?渍(CO2)/?渍(O2), ?渍(CO)/?渍(O2)) of coal spontaneous combustion temperature and the temperature range and gas index critical value of graded early warning were determined, realizing the four grades early warning of coal spontaneous combustion. Finally, a grading prevention and control method for coal spontaneous combustion is proposed for outburst coal seam groups, such as “strengthening coal spontaneous combustion prediction and forecasting, nitrogen injection to prevent and extinguish fires, dynamic advancing, air leakage plugging, or gel/polymer colloid injection”, which effectively solves the problem of early warning and control of coal spontaneous combustion in coal seam groups in outburst mines.

Volatile organic compounds (VOCs) are typical pollutants with hazards for humans and the environment, which can be efficiently mitigated by catalytic combustion. Fe2O3‐based catalysts are a promising choice due to their low cost and strong redox ability. Several attempts have been made to promote the catalytic performance for Fe2O3‐based catalysts at low temperatures. This review summarizes the research progress on Fe2O3‐based catalysts for the oxidation of toluene, one of the most common and harmful VOC. Firstly, the structural properties and catalytic performances for Fe2O3‐based catalysts have been summarized, and the reaction mechanisms for toluene oxidation on the surface of Fe2O3‐based catalysts were detailed to comprehend the role of oxygen vacancies. Then, the modification for single Fe2O3 catalysts, including synthesis parameters, structure and morphology control, is introduced to reveal the correlation between physicochemical properties of catalysts and their activity for toluene oxidation. In addition, composite Fe2O3 catalysts, which can promote catalytic performance significantly by the synergetic effect between different components, were presented in detail. Moreover, waste‐derived Fe2O3 catalysts with sustainable merit as converting waste into worth have been discussed. Finally, the advanced machine learning tools, which are helpful in accelerating catalyst design, configuration optimization and reactivity prediction, have been introduced as an emerging research opportunity for the future. [ABSTRACT FROM AUTHOR]

Aiming at the current environmental problems, the thermal oxidation treatment for industrial VOCs emission is a common and effective measure. This paper studies on the optimization effect of one optimization method for direct VOCs thermal oxidation of a color aluminum spraying production line based on Aspen-Plus. According to the direct VOCs thermal oxidation process with a 30000 m³/h circulating air volume, propose the flue gas reflux and coating room drainage technology. Use the second law of thermodynamics, and the exergy flow analysis shows the methane consumption could be reduced 12%. Carbon emissions also decreased significantly, with 3.42% reduction. These findings are practical for industrial production cost saving and environmental protection problems solving.

In this study, we firstly used 1-carboxyethyl-3-methylimidazolium ionic liquid as a capping agent to terminate a binary linear polyimide containing different groups such as ether bonds, carbonyl groups, and fluorine, and prepared six kinds of polyimides capped with ionic liquids (IL-PI). The mechanical properties of the polyimide membranes capped with ionic liquids were higher than those of the uncapped polyimide membranes. The elastic modulus of polyimide membrane from 1,3-bis (4-aminophenoxy) benzene (BPDA) and 3,3′4,4′-benzophenone tetracarboxydianhydride (BTDA) by using ionic liquid as the end capping agent (IL-BPDA-BTDA) was 2012 MPa, which is about 70 times higher than that without the end capping agent. In a TG test, all polyimides capped by ionic liquids showed good thermal properties. The residual amount of the polyimides was more than 40% at 1000 °C, which was higher than the other uncapped polyimides. In conclusion, polyimide membranes with high temperature resistance and high mechanical strength were prepared through an ionic liquid termination method. [ABSTRACT FROM AUTHOR]