为了研究表面活性剂对中阶煤表面关键官能团的影响，选取12种表面活性剂对原煤进行处理，采用红外光谱仪对煤样表面微化学结构进行测定；运用红外半定量参数法计算成熟度、脂肪链长、芳香度、缩合度4个结构参数；根据煤样化学结构参数的变化研究表面活性剂对煤吸附甲烷能力的影响。结果表明：表面活性剂未改变煤的结构，却对煤中的吸收峰强度和官能团比例产生了影响；经过表面活性剂的处理，煤样的成熟度降低、脂肪链变短、芳香度增加、缩合度增强；经过质量分数为1%的APG0814溶液处理的煤样，成熟度参数提高了0.31，脂肪链长参数降低了0.25，芳香度参数提高了0.18，芳环缩合度参数提高了0.37；考虑结构参数与甲烷吸附能力的联系，得出质量分数为1%的APG0814溶液对煤的吸附能力影响最大，促进了煤对甲烷的解吸。

In order to study the effect of surfactants on the key functional groups on the surface of medium rank coal, 12 kinds of surfactants were selected to treat the raw coal, and the microchemical structure of the surface of the coal samples was determined by infrared spectroscopy. Using infrared semi-quantitative parameterization, four structural parameters, namely maturity, fatty chain length, aromaticity and condensation, were calculated; the effects of surfactants on the methane adsorption capacity of coal were investigated according to the changes of the chemical structural parameters of the coal samples. The results showed that the surfactant did not change the structure of the coal, but affected the intensity of the absorption peaks and the ratio of functional groups in the coal. After treatment with surfactants, the maturity of coal samples decreased, the fatty chain became shorter, the aromaticity increased, and the condensation was enhanced; in particular, the maturity parameter of the coal sample treated with 1% APG0814 solution increased by 0.31, the fatty chain length parameter decreased by 0.25, the aromaticity parameter increased by 0.18, and the aryl cyclic condensation parameter increased by 0.37, and the consideration of the structural parameter and the methane adsorption ability linkage, it was concluded that the concentration of 1% APG0814 solution had the greatest effect on the adsorption capacity of coal and promoted the desorption of methane from coal.