The influence of polyethyleneimine type and molecular weight on the CO2 capture performance of PEI-nano silica adsorbents

Pelletization of Immobilized Amine Carbon Dioxide Sorbents with Fly Ash and Poly(vinyl chloride)

“…The lower capacity of PEI 800 ‐S than those of TEPA‐S and EI 423 ‐S is attributed to the high viscosity of the large impregnated PEI 800 (800 g gmol −1 , ≥500 cP) molecules compared with those of TEPA (189.3 g gmol −1 , 54 cP) and EI 423 (423 g gmol −1 , 200 cP). Both slower CO 2 diffusion kinetics and diminished access to some of the amine groups of the immobilized amine sorbents have been attributed to higher amine viscosity. The slightly low capture capacity for E100‐S (250–300 g gmol −1 number average, 231 cP) could result from the diminished access of CO 2 to the higher‐molecular‐weight amines of the mixture or unfavorable CO 2 adsorption to cyclic amines, which could be weaker bases than the aliphatic amines.…”

“…Single-cycleC O 2 capture tests of the four approximately 50 wt %a mine/silica sorbents showed that their adsorption capacities were 2.91 (TEPA-S), 2.90 (EI 423 -S;E I 423 = ethylenimine oligomer mixture, M w = 423), 2.23 (PEI 800 -S;P EI 800 is PEI with M w = 800), and 2.61 mmol CO 2 g À1 (E100-S,E 100 is am ixture of linear, branched, and cyclic amines). Thel ower capacity of PEI 800 -S than those of TEPA-S and EI 423 -S is attributed to the high viscosity of the large impregnated PEI 800 [11] and diminished access to some of the amine groups of the immobilized amine sorbents [12] have been attributed to higher amine viscosity.T he slightly low capture capacity for E100-S( 250-300 ggmol À1 number average,2 31 cP) could result from the diminished access of CO 2 to the higher-molecular-weight amines of the mixture or unfavorable CO 2 adsorption to cyclic amines,which could be weakerbasesthan the aliphatic amines.O wing to their high CO 2 capacities,t he TEPA-S and EI 423 -S sorbents were used to prepare the PVC/FA/sorbent pellets.…”

Comparative Study of Molecular Basket Sorbents Consisting of Polyallylamine and Polyethylenimine Functionalized SBA‐15 for CO2 Capture from Flue Gas

“…[54] Other values between 60-71 kJ mol CO2 À1 werea lso reported over PEI/silica sorbents. [55,56] Over the PAA(50)/SBA-15 sorbent, the heat of sorption reached 120 kJ mol CO2 À1 ,much higher than that of PEI-II(50)/SBA-15, implying that the interaction between CO 2 and amine groups in PAA(50)/SBA-15 is much stronger than that of PEI-II(50)/SBA-15. This is reasonable as PAAc ontains solely primary amine whereas PEI-II contains mainlys econdary amine groups with 25 %t ertiary amines and 25 %p rimary amines.…”

Development of monolithic adsorbent via polymeric sol–gel process for low-concentration CO2 capture

“…One way to enhance CO 2 adsorption capacity and selectivity is to immobilize amine compounds in highly porous materials, such as the mesoporous silicas of SBA-15 and MCM-41, to form new amine-based adsorbents [11,[18][19][20][21][22][23][24]. Furthermore, water is positive to CO 2 adsorption capacities of amine-based adsorbents due to the formation of carbamate intermediates [20,21].…”