DIPA改性SBA-15介孔分子筛用于CO_2/CH_4分离的性能研究

CH4和CO2的大量排放是造成温室效应的主要因素,在全世界范围内对排放的CH4和CO2进行回收和利用是非常必要的。变压吸附是有效的气体分离技术,而高选择性吸附剂是变压吸附技术的关键。将DIPA(二异丙醇胺)负载在介孔分子筛上,使介孔分子筛的介孔和胺作用结合起来,合成了高选择性CO2/CH4分离吸附剂。首先以水热法合成SBA-15介孔分子筛,通过表征分析,其具有高度有序的六方结构,而DIPA改性后的SBA-15仍然保持介孔分子筛的有序结构,且DIPA基本都进入孔道内。SBA-15经DIPA改性后,CO2/CH4选择分离性能大大提高,分离因子达46.75,吸附的CH4可完全再生,吸附的CO2只能部分再生。负载DIPA对CH4的吸附容量没有明显影响,但大大提高CO2的吸附容量。在6次稳定性实验后,对CH4、CO2的吸附量保持稳定,CH4/CO2的分离因子在15.5左右。随操作温度的升高,DIPA改性SBA-15对CO2吸附容量增大,通过单塔吸附再生的性能比较,45℃时CO2吸附再生的综合性能最好。

Study on CO_2/CH_4 separation properties of DIPA-modified mesoporous molecular sieve SBA-15

Accumulation of CO2 and CH4 in the atmosphere is considered responsible for greenhouse effect and the world cli-mate change,therefore,capture of CO2 and CH4 from the mixture gas becomes an inevitable task.Pressure swing adsorption(PSA) is an effective method to separate mixture gas,and its key is to find a selective and efficient adsorbent.A modified adsorbent for high selective separation of CO2/CH4 was prepared by amine-functionalizing the hydrothermal synthetic mesoporous silica SBA-15 with DI-PA.The mod...