Preparation Of Amine-functionalized Porous Materials And Their Application For CO₂ Adsorption

The increasing carbon dioxide （CO₂） has been as a primary cause of global climate change. CO₂ capture by solid sorbents based on amines immobilized in porous solids has been an increasingly active method. A variety of amines, supports and immobilizing techniques have been tested and the results have been quite promising.This paper respectively using P123 as a soft template and tetraethylorthosilicate （TEOS） as a silicon source to synthesize mesoporous silica materials SBA-15. SB A-15 was respectively modified with triethylenetetramine （TETA） and tris（2-aminoethyl）amine （TAEA） witch are two isomers of amine as sorbents for CO₂ capture. SBA-15 was impregnated with three different types amines nonylamine （P）, N-methyl-Octylamine（S） and tripropylamine（T） respectively as adsorbents for CO₂ capture. The microporous MOF materials MIL-101 as the supports, modifying with TETA, TEPA and PEI to prepare sorbents for CO₂ capture. The morphology and properties of the materials were characterized by scanning electron microscopy, N2 absorption/desorption, thermal gravimetric, infrared and other instruments, and their carbon dioxide adsorption properties were also tested.1. Preparing SBA-15 sorbents which are impregnated with TETA and TAEA for CO₂ adsorption test. It was found that the amine structure dramatically influences the CO₂ capture performance of sorbents. The results demonstrate that SBA-TETA based sorbents show better CO₂ capture performance than SBA-TAEA based sorbents in the absence of moisture, while SBA-TAEA based sorbents are slightly better than SBA-TETA based sorbents in the presence of moisture. This may be explained by the fact that tertiary amine groups can not capture CO₂ effectively in the absence of moisture but can work well in the presence of moisture.2. Preparation of SBA-15 witch are modified with different types amines nonylamine （P）, N-methyl-Octylamine（S） and tripropylamine（T） as sorbents for CO₂ capture. The results demonstrate that SBA-P show better CO₂ capture performance than SBA-S and SBA-T in the absence of moisture. For pure amines, P show better CO₂ capture performance than T in the absence of moisture, while T is slightly better than P in the presence of moisture. This study may help us to design suitable solid amine sorbents for CO₂ capture under different conditions.3. Using microporous material MIL-101 as a support witch is loaded of three different organic amines （TETA, TEPA and PEI） for the CO₂ adsorption test. CO₂ adsorption experiments showed that the adsorption performance of the adsorbent increases with amine load capacity. Under the same load capacity, MIL-101 witch is modified with TETA, TEPA and PEI has the different CO₂ adsorption capacity and the CO₂ adsorption capacity of the MIL-TETA, MIL-TEPA to MIL-PEI is gradually decreased, and compared to the MIL-TETA and MIL-TEPA,the MIL-PEI has the best cycle performance.