Effect of Chain Topology of Polyethylenimine on Physisorption and Chemisorption of Carbon Dioxide

Abstract

Polyethylenimine (PEI) is a promising candidate for CO2 capture. In this work, the physisorption and chemisorption of CO2 on various low-molecular-weight PEIs are investigated to identify the effect of chain architecture on sorption. The reliability of theoretical calculations are partially supported by our experimental measurements. Physisorption is calculated independently by the reference interaction-site model integral equation theory; chemisorption is distinguished from the total sorption given by the quantum density functional theory. It is shown that, as the chain length increases, both chemisorption and physisorption drop off nonlinearly, but the decay amplitude of chemisorption is more apparent. Conversely, as the amine group approaches the central triamine unit of each oligomer, the sorption capacity decreases, affecting the sorption equilibrium in a complex way. This arises from the cooperative contribution of an increased steric effect and renormalized electronic distribution.

Determination and Correlation of Poly(vinylpyrrolidone) Solubility in Subcritical 1,1,1,2-Tetrafluoroethane

“…The solubility data in Table also shows that under the same experimental temperature and pressure condition, the solubility of PVP decreases when its molecular weights increase, and the tendency of solute solubility is the same as those reported in the literature. , On the one hand, this can be attributed to the fact that the interactions between solute molecules become stronger with increasing molecular weights, which makes it much more difficult for the solute to dissolve; on the other hand, both phenomena can be explained by entropythe Gibbs free energy (Δ G ) of a single polymer chain and the steric hindrance of the polymer increase with increasing molecular weight . According to Flory’s theory (eq ), the chaos degree of solute molecule (Δ S ), decreases with increasing Δ G .…”

Solubility of Polyacrylamide in Supercritical Carbon Dioxide

“…The Gibbs free energy (Δ G ) of single polymer chain and steric hindrance of ploymer both increase with molecular weight increasing and Δ S , which represents chaos degree of solute molecules, decreases with Δ G increasing. Therefore, solute solubility decreases with molecular weight increasing.…”

Size effect on the adsorption and dissociation of CO2 on Co nanoclusters

“…In recent years, in addition to the capture and storage technology [1][2][3][4][5][6][7], the recycling technology for CO2, a major greenhouse gas, has attracted considerable interest. A promising route for relieving the greenhouse effect is to convert CO2 into CO, which has been widely investigated in the recycling technology.…”