氨改性介孔SiO_2用于CO_2/N_2变压吸附分离

Amine-Functionalized Mesoporous Silica for CO_2 and N_2 Separation by PSA

在323.15,K下,以月桂酸为结构导向剂(SDA)、γ-氨丙基三乙氧基硅烷为助结构导向剂和硅酸乙酯为硅源,采用阴离子表面活性剂法直接合成氨改性介孔SiO2(AMS)用于CO2/N2变压吸附分离.对样品进行低温N2吸附脱附、X射线衍射(XRD)和透射电镜(TEM)表征,然后用动态法测量其CO2、N2穿透曲线并计算吸附量.结果发现,在323.15,K、常压下合成吸附剂AMS对CO2/N2的吸附量分别为0.60,mmol/g和0.03,mmol/g.采用抽真空的方法对吸附剂进行再生,发现75%以上的吸附态CO2能够解吸,经过多次吸附/解吸循环CO2吸附特性不变.同时利用Aspen adsim软件对吸附过程进行模拟,模拟结果与实验数据吻合良好.

Amine-functionalized mesoporous silica（AMS） was prepared with lauric acid as template, r- aminopropyl-triethoxysilane as co-structure directing agent, tetraethyl orthosilicate as silica source and applied to CO2/N2 separation by pressure swing adsorption （PSA） at 323.15 K. The amine-functionalized mesoporous silica was characterized by nitrogen physisorption, X-ray diffraction （XRD） and transmission electron microscope （TEM）. The adsorption capacity for CO2 and N2 were measured by dynamic method. The results show that at 323,15 K and under the atmospheric pressure, the adsorption capacity of AMS for CO2 and N2 are 0.60 mmol/g and 0.03 mmol/g, respectively. The adsorptive saturated adsorbents can be regenerated by vacuuming, and above 75% of adsorbed CO2 can be desorbed. The CO2 adsorptive capacity remains unchangeable after a long adsorption/desorption run. The proc- ess has been simulated with Aspen-adsim and the simulation results agree well with the experimental data.