氨基改性蠕虫型介孔SiO_2吸附CO_2性能的研究

CO_2 capture of amine loaded on worm-hole mesostructured silica

采用D2000为模板剂,TEOS为硅源,在中性的条件下合成了具有较大孔径的蠕虫型介孔SiO2(MSU-J),并采用四乙烯五胺(TEPA)通过物理浸渍的方法制备不同质量分数的TEPA改性的MSU-J,得到具有高吸附量的CO2吸附剂。利用FT-IR,N2吸附/脱附及TG对所制备的样品进行表征。CO2的吸附试验是在不同氨基质量分数(20%,30%,50%,70%)以及不同温度下测试。吸附实验表明,浸渍TEPA后,吸附剂由单纯的物理吸附转变为以氨基为活性中心的化学吸附,且随着TEPA浸渍含量的增加吸附量先增加后降低,当TEPA负载量(质量分数)为50%时,吸附量可达到164.3 mg/g。温度对吸附剂的吸附性能也有一定的影响,最佳的吸附温度为25℃,这与吸附机理有关,随着温度的升高,反应向解吸附方向移动。循环性试验表明,所制备的吸附剂具有良好的循环性能,材料重复使用6次,对CO2吸附性能只有少量的下降,这可能是由于TEPA的挥发或者部分分解引起的。

The novel CO2 adsorbents with high capture efficiency were prepared through a supramolecular hydrogenbonding assembly pathway from D2000 and TEOS. Tetraethylenepenta mine（ TEPA） was employed to functionalize the MSU-J silica via wet impregnation method. The synthesis way is environmentally friendly due to the absence of the potential pollutants such as toluene. The resultant samples were characterized by FT-IR,N2 adsorptiondesorption and TG. CO2 capture was investigated at different temperatures and TEPA loadings（ mass fractions：20%,30%,50%,70%）. The sample impregnated by 50% TEPA showed the highest adsorption capacity,with the value of approximately 164. 3 mg / g at 25 ℃ and 0. 1 MPa,due to its higher a mino-groups content and superior structure property. Also,the adsorption temperature played important role on the adsorption capacity,which indicated that the optimal adsorption temperature was 25 ℃. The resultant adsorbent material exhibited satisfactory performance even after 6 adsorption-regeneration cycles.