Table 2.

Summary of selected carbonaceous adsorbents for CH₄ purification.

Sample ID	Uptake (mmol g−1)			Qst (kJ mmol−1)		Selectivity		Ref.
	CH4	N2	CO2	CH4	CO2	SCH4/N2	SCO2/CH4
PCNPsa	1.17	0.28	—	22.3	—	10d	—	[77]
GOC-2a	1.82	0.5	—	22.1	—	5.8e	—	[78]
SC-6a	1.86	0.6	—	24.9	—	5.7e	—	[79]
PRC-850a	1.12	0.38	—	23	—	5.4d	—	[80]
PSb	1.38	0.45	3.63	—	—	3.1	15g	[81]
GLb	0.45	0.17	1.65	—	—	2.7	54g
OTS-1-550a	1.12	0.3	2.8	25	37.3	5.9e	7.4g	[82]
OTS-2-650a	1.67	0.5	3.96	24.7	33.8	5.2e	4.1g
OTSS-3-350a	0.9	0.26	2.83	—	39.2	5.6e	9.5i	[83]
OTSS-2-450a	0.93	0.3	2.94	—	47	4.9e	12.8i
CGUC-0.5-6a	0.9	0.2	3.4	—	31	6.7e	34.9h	[84]
CGUC-1-6a	1.01	0.2	3.26	—	27.5	5.9e	16.9h
SNMC-1-600a	1.45	0.5	3.98	—	27.5	5.1e	6.9h	[74]
SNMC-2-600a	1.57	0.5	4.24	—	26.4	4.2e	4.3h
SNMC-3-600a	1.17	0.4	3.0	—	23.3	3.6e	3.2h
Co-NDPC-500a	1.0	0.26	3.5	27	35	3.9f	10.4e	[85]
Co-NDPC-600a	1.2	0.27	5.3	28	53.8	4.4f	11.4e
CC-PNPc	2.20	—	3.7	—	—	—	15.9i	[86]
P-CC-PNPc	4.26	—	7.5	—	—	—	5.2i
C30-CC-PNPc	7.02	—	11.9	—	—	—	4.3i
C85-CC-PNPc	5.35	—	8.9	—	—	—	4.8i
Chit_supCO2_P800a	0.01	—	1.37	—	—	—	137j	[87]
Chit-PMO_P800a	0.01	—	0.30	—	—	—	30j
Chit-PMO_P800_crusheda	0.14	—	1.01	—	—	—	7.2j
C1000a	1.75	—	3.7	17.4	20.7	—	28e	[88]
PHAa	0.63	—	1.6	22.5	33.5	—	7.2e	[89]
NAHA-1a	1.65	—	3.75	23	29.7	—	7e
NAHA-2a	1.5	—	4	23.5	29	—	6e

Gas uptake at ^a298 K and 100 kPa, ^b313 K and 100 kPa, and ^c298 K and 20 bar. IAST predicted selectivity for separation of CH₄/N₂ with mole ratios of ^d30/70 and ^e50/50. ^fUptake ratio of CH₄/N₂ as separation selectivity. IAST predicted selectivity for separation of CO₂/CH₄ with mole ratios of ^g50/50, ^h40/60, and ⁱ10/90. ^jUptake ratio of CO₂/CH₄ as separation selectivity.