Fig 1.
Chemical structure of ion exchange resin containing two side chains.
The exchanged anion is CO32-.
Fig 2.
Schematic of experimental device.
The CO2 concentration can be tracked at inlet and outlet of the chamber of sorbent sample. The amount of absorbed CO2 can be calculated by measuring the CO2 concentration change with time. Dew point generator can control the water vapor concentration in the system.
Fig 3.
The schematic of the experimental device.
The total amount of CO2 in the sample and in the gas volume is constant. The process of CO2 absorption/desorption can be identified in the experimental device.
Fig 4.
SEMs of P-100 sorbents treated with different water temperatures.
(A) 25°C-water-treated sample P-100-25C, (B) 50°C-water-treated sample P-100-50C, (C) 90°C-water-treated sample P-100-90C.
Fig 5.
Comparison of CO2 absorption half times and capacities of different sorbents.
Hyperbranched aminosilica (HAS) with different amine loading (-), PEI/silica materials (□), and moisture-swing Ion Exchange Resin (IER) (●). The number of half time and absorption capacity of each absorbent has been shown in S1 Table.
Fig 6.
Comparison of kinetic model and experimental data for absorption performance of P-100-90C absorbent.
Fig 7.
CO2 desorption process of four absorbents (A) P-100-90C absorbent, (B) P-100-50C absorbent, (C) P-100-25C absorbent, (D) I-200 absorbent. Left Y-axis is absorbent weight, and right Y-axis is CO2 concentration.
Table 1.
Diffusion coefficients of water, equilibrium times of water and CO2 in four samples.