Table 2.

Separation efficiency of $\mathbf{C}{\mathbf{O}}_2$ from ${\mathbf{H}}_2/\mathbf{C}{\mathbf{O}}_2$ mixture through hydrate formation^a

Promotor	Promotor concentration (Mol%)	Temperature (K)	Pressure (MPa)	Separation efficiency	Label	Reference
CP	0.	276.15	6	90.9	a	(Yu et al., 2020b)
CP	1.33	276.15	6	94.8
CP	0.34	276.15	6	98.8
TBAB TBAB TBAB	0.29 0.5 1	278.15 280.35 282	3 3 3	23.8 56.88 54.63	b n	(Li et al., 2011)
THF (fresh-water) THF (memory-water) THF (memory-water)	5.56 5.56 5.56	284.85 286.8 285.85	6 6 6	63 63 69	c o z	(Li et al., 2019)
TBAB TBAB TBAB/DMSO TBAB/DMSO	0.4 0.256 0.29/0.71 0.4/0.071	285.95 286.15 277.15 285.25	2.51 2.5 2.5 2.5	46 52 68 63		(Xia et al., 2016)
TBAB	0.29	275.15	3.5	64	e	(Xu et al., 2013)
${\text{C}}_3{\text{H}}_8$ ${\text{C}}_3{\text{H}}_8$	2.5 1.2	273.7 273.7	3.8 3.5	47 32	f g	(Babu et al., 2013)
TBAB TBAB	0.29 0.29	275 284	5 3	67.5 26	h i	(Yu et al., 2018)
None		277.15	4	67	j	(Yang et al., 2015)
${\text{TBANO}}_3$ TBPB	2 3.1	275 275	2 2	67 61	k l	(Fukumoto et al., 2015)
TBAB	0.1	278	2.5	56	m	(Horii and Ohmura, 2018)

^aThe labels in the table correspond to the bars in Figure 7.