Comprehensive Study of the Impact of Steam on Polyethyleneimine on Silica for CO₂ Capture

Abstract

An amine sorbent, prepared by impregnation of polyethyleneimine on silica, was tested for steam stability. The stability of the sorbent was investigated in a fixed bed reactor using multiple steam cycles of 90 vol % H2O/He at 105 °C, and the gas effluent was monitored with a mass spectrometer. CO2 uptake of sorbent was found to decrease with repeated exposure to steam. Characterization of the spent sorbent using N2 physisorption, SEM, and thermogravimetric analysis (TGA) showed that the decrease in CO2 loading can possibly be attributed to a reagglomeration of the amine in the pores of the silica. No support effect was found in this study. The commercial SiO2 used, Cariact G10, was found to be stable under the conditions used. While it was found that subjecting the sorbent to several steam cycles decreased its CO2 uptake, a continuous exposure of the sorbent to steam did not have a significant performance impact. A silanated sorbent, consisting of a mixture of PEI and aminopropyl-triethoxysilane on SiO2 support, was also investigated for steam stability. Similarly to the nonsilanated sorbent, the CO2 loading of this sorbent decreased upon steam exposure, although a mechanism for this change has not been postulated at this time.

Stability of a Benzyl Amine Based CO2 Capture Adsorbent in View of Regeneration Strategies

“…However, the presence of water in the process may have an influence on desorption kinetics for some types of supported amine sorbents. 32,49 Further study on the effect of steam in terms of desorption kinetics is required and ongoing.…”

Insights into the Hydrothermal Stability of Triamine‐Functionalized SBA‐15 Silica for CO2 Adsorption

“…[21] The alumina-supported adsorbent outperformed its SBA-15 counterpartb yawide margin, showing a CO 2 uptake loss of 16.3 %a so pposed to 67.1 %f or SBA-15. [22] studied the steam stability of PEI-impregnated grade G-10 silica (Fuji Silysia Chemical Ltd.) throughe ight consecutivea dsorption/steam regeneration cycles. [21] The authors attributed the poor performance of the impregnatedS BA-15 following exposure to steam to structural collapse or restructuring of the support and amine leaching.…”

“…[21] When 400 ppm CO 2 in N 2 was used as adsorbate to mimic direct air capture,t he differencew as even more pronounced, with an uptake loss of 25.2 %f or the former support relative to 81.3 %f or the latter one. [22] Ruling out the first four factorst hrough as eries of experiments,t he authors speculated that amine reagglomeration on the silica support might have been the reason. As no significant change in amine loading was observed following exposure to steam, the authors suggested that the amine might have leachedo ut of the pores, coveringt he external surface of the support.…”

“…[21] The authors attributed the poor performance of the impregnatedS BA-15 following exposure to steam to structural collapse or restructuring of the support and amine leaching. [22] Sandhu et al [19] explored the stabilityo fP EI-impregnated commercial grade Q-10 silica (Fuji Silysia ChemicalL td.) Although not ex-plicitly mentioned, the much smaller pore size of the SBA-15 support (6.8 nm) relative to the g-alumina support (17.3 nm) [21] is consistentw ith the vast differencei nt he performance of the adsorbentsb ecause of enhanced diffusion resistance.…”

Adsorptive removal of carbon dioxide using polyethyleneimine loaded glass fiber in a fixed bed

“…4(a), (b)), the adsorption peaks at 3349 cm −1 , 3284 cm −1 and 914 cm −1 were assigned to the asymmetric bending and stretching vibration of Si-OH, which is the main structure in the GF substrate. In comparison to the GF, the PEI-loaded GF exhibited new peaks located at 2945 cm −1 (symmetric stretching of -CH 2 -), 2837 cm −1 (asymmetric stretching of -CH 2 -) and 1671 cm −1 (bending vibration of -N(R)H), which indicated that PEI were successfully introduced [39]. The spectra of the PEI-loaded GF before ( Fig.…”