高压甲烷与二氧化碳吸附对煤体官能团特性的影响研究

摘要

为了研究高压甲烷与二氧化碳吸附对煤体官能团特性的影响,选取长焰煤和无烟煤两种煤样,进行了2、4、6 MPa压力等级下甲烷与二氧化碳的吸附处理,并利用傅里叶红外光谱( FTIR)分析了煤吸附气体前后官能团的变化,结果表明:长焰煤中含氧官能团明显多于无烟煤,但对于两种煤样而言,不论是吸附何种压力的甲烷还是二氧化碳,吸附前后煤中官能团的分布并没有出现明显的变化,没有任何新的吸收峰出现,或原有的吸收峰消失,这说明在通常的试验条件与现场环境中,在煤吸附甲烷与二氧化碳的过程中并没有发生化学吸附,煤吸附甲烷与二氧化碳可以认定为纯物理吸附.%In order to study the influence of high-pressure methane and carbon dioxide absorption on the functional groups of coal, long-flame coal and anthracite coal were selected, the adsorption treatment was carried out to them with methane and carbon dioxide at the pressure levels (2 MPa, 4 MPa and 6 MPa), and analysis was made on the changes of functional groups before and after gas adsorption by means of Fourier transform infrared spectroscopy ( FTIR) . The results showed that the oxygen-containing functional groups in the long-flame coal were significantly more than that in the anthracite coal, but for these two kinds of coal, no matter what the methane at any pressure and carbon dioxide were absorbed by them, the distribution of functional groups in them did not change significantly before and after adsorption, no new absorption peak appeared, or the original absorption peak disappeared, this indicated that chemical adsorption did not take place in the process of methane and carbon dioxide absorption under normal test conditions and in the site environment, so the methane and carbon dioxide adsorption of coal can be regarded as pure physical adsorption.