TEPA在SBA-15(P)上的嫁接形态及其对CO2吸附性能的影响

通过控制浸渍方法和其过程将四乙烯五胺(TEPA)负载到SBA-15原粉上制备氨基功能化的CO2吸附材料TEPA/SBA-15(P).利用X射线衍射(XRD)、氮吸附、元素分析和傅里叶变换红外(FTIR)光谱等手段对各种吸附材料进行表征分析,并对其CO2吸附能力进行评价.结果表明:TEPA乙醇溶液的动态浸渍过程可以使有机胺高度均匀地负载到SBA-15(P)的孔道内,并形成有利于CO2吸脱附的键合形式.提出了TEPA在SBA-15(P)上的键合作用机制,一方面TEPA的端基氨(-NH2)与载体中的表面羟基(-OH)和醚键(C-O-C)形成氢键,提高了TEPA的分散度;另一方面,TEPA乙醇溶液的动态浸渍过程有效地避免了TEPA分子间或分子内氢键的形成,从而使有机胺TEPA氨基官能团具有较高的吸附容量.

Grafting Morphologies of TEPA on SBA-15(P) and Its Effect on CO2 Adsorption Performance

Various amine-functionalized CO2 adsorbents were prepared by incorporating tetraethylene-penthamine (TEPA) onto SBA-15(P) by controlling the impregnation method and its process.The materials were characterized using X-ray diffraction (XRD),N2-adsorption,elemental analysis,and Fourier transform infrared (FTIR) techniques.Their adsorptive capacities were determined by CO2-temperature programmed desorption (TPD).The results indicate that the dynamic impregnation process using a TEPA ethanol solution was successful in loading TEPA into the channels of SBA-15(P).Moreover,bonding formation between the highly dispersed TEPA and SBA-15(P) was facilitated to CO2 adsorption/desorption.Therefore,a binding mechanism is proposed.The-NH2 group of TEPA forms hydrogen bonds with-OH and C-O-C groups on SBA-15(P),which results in the better dispersion of TEPA.However,the dynamic impregnation process for the TEPA ethanol solution can effectively avoid the formation of hydrogen bonds between the intra-and inter-molecules resulting in the high adsorptive capacity of the amino groups in TEPA.