Semiclathrate-based CO2 capture from flue gas mixtures: An experimental approach with thermodynamic and Raman spectroscopic analyses

Structure-driven CO2 selectivity and gas capacity of ionic clathrate hydrates

“…Since CO 2 is suitably incorporated in the ionic clathrate hydrates 28 , 29 , CO 2 capture processes based on ionic clathrate hydrates were proposed 4 , 7 , 16 , 30 – 37 . CO 2 capture from flue gas by ionic clathrate hydrates were reported a lot 4 , 6 , 32 – 37 . Particularly high CO 2 selectivity was found in ionic clathrate hydrates 6 , 30 , 31 , although canonical gas hydrates also have the similarly sized-dodecahedral cages for gas occupancy.…”

Investigation of kinetics of tetrabutylammonium chloride (TBAC) + CH4 semiclathrate hydrate formation

“…Besides, it should be noted that this phenomenon was not the rst time to show up. In 2015, Kim et al 39,40 studied the spectra of (TBAC + CO 2 ) SCHs and (TBAC + CO 2 + N 2 ) SCHs, and the results showed that the addition of TBAC caused a slight shi of wavenumbers from 1275 cm À1 to 1272 cm À1 . Moreover, Hashimoto 50 provided the differences between HS-I SCHs and TS-I SCHs in Raman spectra in 2008.…”

“…4,[39][40][41] Kim et al presented the PXRD patterns of (TBAC + CO 2 ) SCHs and (TBAC + CO 2 + N 2 ) SCHs. 39,40 Oshima et al 41 studied crystallographic properties of (TBAB + TBAC) SCHs through PXRD measurement, and the result demonstrated that the double SCHs were formed with structure of tetragonal one (P4/mmm or P4/m) or orthorhombic one (Pmma) at different salt concentrations. However, these achievements of TBAC did not involve the formation kinetics which were important for hydrate-based applications.…”

Science Walden: Exploring the Convergence of Environmental Technologies with Design and Art

“…Since QAS semiclathrates have small empty cages, which are available for capturing small-sized gas molecules (Figure 4), they can be effectively used for gas storage and separation. QASs are also non-volatile and non-toxic and can thus be used repeatedly without loss in a semiclathrate-based separation process [6,7]. CO2 from biogas (CH4 + CO2) can be separated using semiclathrates because CO2 preferentially occupies the small cages of QAS semiclathrates, as shown in Figure 3.…”

“…Such occupation is due to the higher thermodynamic stability of CO2 in semiclathrates than that of CH4. In this study, tetra-n-butylammonium chloride (TBAC) was used as a semiclathrate former to capture CO2 from biogas because among QASs, TBAC has the highest gas storage capacity and yields the highest equilibrium dissociation temperature [6,7]. …”