自然发火是煤矿常见灾害之一。煤自燃低温阶段CO与C₂H₄作为预测预报的标志气体，CO与C₂H₄在煤中的吸附/解吸影响预测预报准确性。本文以宁夏灵新煤矿不粘煤为研究对象，采用液氮吸附实验、CO与C₂H₄吸附/解吸实验，深入研究了温度、压力、粒径及孔隙结构对CO和C₂H₄在煤中吸附/解吸的影响，并分析了CO和C₂H₄吸附/解吸过程中的吸附热和吸附势特征，结合分子模拟手段，从微观角度探究CO和C₂H₄吸附特征。取得的主要研究成果如下：

（1）实验煤样孔隙结构发育有墨水瓶孔、半开放孔及开放孔，孔径分布以微孔为主；随粒径减小，煤样总孔容和总比表面积增加，其中微孔孔容和比表面积所占比例增大，过渡孔孔容和比表面积所占比例减小，中孔孔容和比表面积所占比例减小。

（2）实验条件下（温度：303.15～333.15K、压力：0.15～0.50MPa），温度越低、压力越大、煤样粒径越小，煤对CO和C₂H₄的吸附能力越强。降压能够促进CO和C₂H₄在煤中解吸，解吸过程存在滞后现象；温度越高、煤样粒径越小，煤对CO和C₂H₄的解吸滞后性越小。煤样孔容和比表面积与CO和C₂H₄饱和吸附量呈正相关关系，与解吸滞后性呈负相关关系。

（3）CO和C₂H₄解吸过程等量吸附热大于吸附过程等量吸附热，说明CO和C₂H₄解吸过程比吸附过程需要更多能量；相同吸附量条件下，煤样粒径越小，等量吸附热越低；CO和C₂H₄吸附/解吸过程的等量吸附热分别介于1.51～18.95 kJ/mol与0.81～14.50 kJ/mol之间，吸附势与吸附相体积呈线性负相关关系，表明煤与CO和C₂H₄分子之间作用力主要为色散力，属于物理吸附。

（4）CO与C₂H₄在煤分子中吸附模拟实验表明：不同温度和压力条件下，CO和C₂H₄在煤分子中吸附规律与实验结果一致；CO和C₂H₄的模拟实验吸附热结果显示，CO和C₂H₄在煤分子中吸附属于物理吸附；CO和C₂H₄与煤分子之间的相互作用能为负，温度相同时相互作用能随压力升高而减小，压力一定时相互作用能随温度升高而增大。

Natural ignition is one of the common disasters in coal mines. CO and C₂H₄ at the low temperature stage of coal spontaneous combustion are used as the marker gases for prediction, and the adsorption / desorption of CO and C₂H₄ in coal affects the prediction accuracy. This paper takes Ningxia Lingxin coal non-stick coal as the research object, adopts liquid nitrogen adsorption experiment, CO and C₂H₄ adsorption/desorption experiment, and deeply investigates the effects of temperature, pressure, particle size and pore structure on CO and C₂H₄ adsorption/desorption in coal, and analyzes the characteristics of adsorption heat and adsorption potential during CO and C₂H₄ adsorption/desorption, and combined with molecular simulation tools to explore the CO and C₂H₄ adsorption characteristics from a microscopic perspective. The main research results obtained are as follows:

(1) The pore structure of the experimental coal samples developed with ink bottle pores, semi-open pores and open pores, and the pore size distribution was mainly micropores; the total pore volume and total specific surface area of the coal samples increased with decreasing particle size, among which the proportion of micropore volume and specific surface area increased, the proportion of transition pore volume and specific surface area decreased, and the proportion of medium pore volume and specific surface area decreased.

(2) Under the experimental conditions (temperature: 303.15～333.15 K, pressure: 0.15～0.50 MPa), the lower the temperature, the higher the pressure, and the smaller the particle size of the coal sample, the stronger the adsorption capacity of coal to CO and C₂H₄. Depressurization can promote the desorption of CO and C₂H₄ in coal, and there is a hysteresis in the desorption process; the higher the temperature and the smaller the particle size of the coal sample, the smaller the hysteresis in the desorption of CO and C₂H₄ by coal. The pore volume and specific surface area of coal samples showed a positive correlation to the saturation adsorption of CO and C₂H₄, and a negative correlation to the desorption hysteresis.

(3) The equivalent heat of adsorption of CO and C₂H₄ desorption process is larger than the equivalent heat of adsorption of adsorption process, which indicates that the desorption process of CO and C₂H₄ requires more energy than the adsorption process; the smaller the particle size of the coal sample, the lower the equivalent heat of adsorption under the condition of the same adsorption amount; the equivalent heats of adsorption for the CO and C₂H₄ adsorption/desorption processes ranged from 1.51 to 18.95 kJ/mol and 0.81 to 14.50 kJ/mol, respectively, and the adsorption potential is linearly and negatively correlated with the volume of the adsorbed phase, which indicates that the force between coal and CO and C₂H₄ molecules is mainly dispersion force and belongs to physical adsorption.

(4) The simulation experiments of CO and C₂H₄ adsorption in coal molecules showed that: the adsorption pattern of CO and C₂H₄ in coal molecules under different temperature and pressure conditions is consistent with the experimental results; the simulated experimental heat of adsorption results for CO and C₂H₄ show that the adsorption of CO and C₂H₄ in the coal molecules belong to physical adsorption; the interaction energy between CO and C₂H₄ and coal molecules is negative, and the interaction energy decreases with increasing pressure when the temperature is the same, and increases with increasing temperature when the pressure is certain.

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