结合改性硅胶对模拟煤层气中CH_(4)/CO_(2)的吸附分离研究

Adsorption and Separation of CH_(4)/CO_(2)in Simulated Coalbed Methane with Modified Silica Gel

利用碱土金属(Ba)和乙醇胺(MEA)对硅胶吸附剂(SGA)进行结合改性得到改性硅胶吸附剂(SGA-MEA-Ba),对改性前后硅胶的理化性质、再生性能及其对模拟煤层气中CH_(4)/CO_(2)混合气的分离效果进行分析。结果表明,经过碱土金属(Ba)和乙醇胺结合改性的SGA的比表面积和总孔体积均有所下降;SGA改性前后其主要官能团基本相同,改性后出现了—NH_(2);除了改性后的SGA中多了Ba元素的衍射峰外,改性前后其余物相结构没有特别的改变。经过碱土金属(Ba)和乙醇胺的结合改性的SGA对CO_(2)的吸附量增大,从1.34mmol/g增加到了3.30mmol/g,同时对CO_(2)/CH4混合气的分离效果增强,对CO_(2)/CH4混合气的分离比从9.14提高到了9.92。

The modified silica gel adsorbent(SGA-MEA-Ba)was obtained by combining alkaline-earth metal(Ba)and ethanolamine(MEA)to modify silica gel adsorbent(SGA).The physical and chemical properties,regeneration performance of the silica gel before and after modification were analyzed,as well as their separation effects of CH_(4)/CO_(2)mixture in simulated coalbed methane.The results are concluded as follows.Firstly,the specific surface area and total pore volume of the SGAMEA-Ba decrease.Secondly,the main functional groups of the SGA before and after modification are basically the same,and—NH2appears after modification.Thirdly,except for the diffraction peak of Ba element in the SGA-MEA-Ba,there is no special change in the other phase structure before and after modification.Finally,for the SGA-MEA-Ba,the adsorption capacity of CO_(2)increased from 1.34mmol/g to 3.30mmol/g,and the separation ratio of CO2/CH4mixture was enhanced from 9.14to 9.92.