Insights into the enhancement of CO2 adsorption on faujasite with a low Si/Al ratio: Understanding the formation sequence of adsorption complexes

Quantitatively Understanding the Insights into CO2 Adsorption on Faujasite from the Heterogeneity and Occupancy Sequence of Adsorption Sites

“…Both samples were pretreated at a slowly increasing temperature to remove adsorbed H 2 O that can damage a zeolite at a high temperature. The pretreatment has been detailed in our previous study . An Autosorb-iQ3 physisorption machine (Quantachrome Instruments) was used to obtain the CO 2 adsorption isotherms for the two samples at 273, 293, and 313 K. For each test, approximately 0.4 g of a sample was loaded into the machine and degassed at 623 K under vacuum conditions for 5 h. The temperature was increased at a rate of 2 K/min to protect the sample.…”

“…The chemical formula used for NaX was Na 88 Al 88 Si 104 O 384 , corresponding to the Si/Al ratio (1.18) of a sample that we previously characterized experimentally. 43 The fixed NaX framework has been reported by Olson et al 44 The distribution of Si atoms was obtained by randomly substituting eight Al atoms by Si atoms in Na 96 Al 96 Si 96 O 384 , following Loẅenstein's rule. 45 It has been reported that this random process does not considerably influence the simulation results.…”

“…A CO 2 molecule with two adjacent cations at site SIII (or SIII′) was considered to be adsorbed in a dual-cation adsorption site, which was labeled The pretreatment has been detailed in our previous study. 43 An Autosorb-iQ3 physisorption machine (Quantachrome Instruments) was used to obtain the CO 2 adsorption isotherms for the two samples at 273, 293, and 313 K. For each test, approximately 0.4 g of a sample was loaded into the machine and degassed at 623 K under vacuum conditions for 5 h. The temperature was increased at a rate of 2 K/min to protect the sample. After degassing, the sample tube was maintained at the target temperature.…”

Adsorption of Carbon Dioxide on Shirasu‐based Materials

“…Adsorption processes of carbon dioxide in solution [1][2][3][4][5] and on solid materials [6][7][8] has been proposed as promising processes for storing carbon dioxide excessively emitted into the atmospheric environment. In the various processes via adsorption, porous solid materials including oxide ceramics such as aluminosilicate including zeolites, [9][10][11][12][13][14][15][16][17][18][19][20][21][22] mesoporous silicas, [23][24][25][26][27][28][29][30] metal oxides, [31][32][33] carbon-based materials, [34][35][36][37][38] and metal-organic-frameworks (MOFs) [39][40][41] have attracted much attention for cyclic adsorption uses in low-cost simple adsorption processes of carbon dioxide.…”

Carbon dioxide capture with zeotype materials

“…55 These results are consistent with data obtained from IR spectra. 108 Recently, Yang et al 104 found five typical Na + –CO 2 adsorption complexes in high-aluminum FAU-type (zeolite X) zeolites, as shown in Fig. 3b.…”