Amine-Modified SBA-15: Effect of Pore Structure on the Performance for CO₂ Capture

Abstract

Several SBA-15 silica materials with different pore structures were synthesized and functionalized with poly(ethyleneimine) (PEI). The as-prepared materials were characterized by XRD, SEM, TG, FT-IR, and N 2 physisorption techniques followed by testing for CO 2 capture using a N 2 stream containing 15.1 v/v% CO 2 in the temperature range of 30-75°C. The results showed that the CO 2 adsorption capacity linearly increased with the total pore volume of the SBA-15 phases in the tested temperature range (R 2 > 0.94). Temperature also showed a strong influence on CO 2 adsorption capacity. SBA-15 material with the largest pore volume (1.14 cm 3 g -1 ) exhibited the largest CO 2 adsorption capacity (105.2 mg g -1 adsorbent) with 15.1 v/v% CO 2 in N 2 at 75°C and atmospheric pressure. Pore size was found not to be the main factor influencing the CO 2 adsorption capacity of these PEI-modified SBA-15 materials. Adsorption-desorption cycles (12) revealed that the adsorbents with PEI loaded inside the pore channels were found to be quite stable, as they retained their CO 2 adsorption capacity with many cycles.

Efficient CO2 sorbents based on silica foam with ultra-large mesopores

“…Yan et al recently studied amine supported sorbents based on bulk SBA-15 and found that the sorbent capacity did increase with the total pore volume of the support. 18 For sorbents based on hierarchical structures, the adsorption contribution from the external surfaces may not be negligible so that eqn (S1) † becomes too complicated and is beyond the scope of the simple analysis presented here. Nevertheless, this analysis suggests that under certain conditions, larger total pore volume of the support is advantageous and can result in a higher theoretical CO 2 capacity.…”

“…In general, large pore size and good pore interconnection tend to improve sorbent capacity. 7,11,[18][19][20] To that end, significant efforts have been directed towards developing supports with optimized structures in order to further improve the performance of sorbents. Mesocellular foams, of sorbents based on hollow mesoporous silica spheres with welldefined sizes and shell thicknesses.…”

CO2adsorption on different organo-modified SBA-15 silicas: a multidisciplinary study on the effects of basic surface groups

“…This facilitates the interaction between the CO 2 and the amino groups and the resulting formation of carbamate groups. 17 Different studies of CO 2 adsorption on SBA--15 silica containing amino species are reported in the literature. For example, Wang et al 3 have grafted SBA--15 silica with 3--aminopropyltrimethoxysilane obtaining a material with CO 2 uptake of ca.…”

N1-(3-trimethoxysilylpropyl)diethylenetriamine grafted ordered mesoporous silica KIT-6 for CO2adsorption

“…Compared with grafting method, impregnation can make more amines loaded on support, but their distribution is inferior because the amine groups often conglomerate [7] . Nowadays, more and more literatures reported on amine grafted MCM series and SBA series for CO 2 adsorption [8] . But only few of them reported on the CO 2 adsorption behavior in amine grafted KIT-6.…”