Asphalt-derived high surface area activated porous carbons for the effective adsorption separation of ethane and ethylene

Facile synthesis of ultramicroporous carbon adsorbents with ultra‐high CH4 uptake by in situ ionic activation

“…Figure S2 presents the N 2 adsorption–desorption isotherms of SCs at 77 K. All the samples exhibited a characteristic type I isotherm (according to the IUPAC classification), with a steeply increasing N 2 adsorption capacity at relatively low pressures, indicative of the characteristic of typical microporous materials 29,30 . Figure 2 shows the pore‐size distributions of SCs, which were calculated using the quenched‐solid density functional theory (QSDFT) based on a slit‐shaped pore model 31,32 .…”

Ethane‐selective carbon composites CPDA@A‐ACs with high uptake and its enhanced ethane/ethylene adsorption selectivity

“…The oxygen content of the samples was significantly higher than nitrogen content. The oxygen and nitrogen contents in CPDA@A‐ACs composites are higher than those in A‐AC materials …”

“…Our previous work indicated that the oxygen/nitrogen sites in the porous carbon were considered holding the key to affect the adsorption behaviors of ethane and ethylene in the material, hence, it is expected to provide better understanding of the adsorption mechanism by qualitatively investigating the interaction energies of these binding sites with computational simulation. In this work, fragment models of CPDA@A‐ACs containing different binding sites (oxygen/nitrogen sites) were constructed, with the dangling bonds terminated by H atoms.…”

“…Its ethane adsorption capacity reached up to 7.93 mmol/g at 100 kPa and 298 K, and its ethane/ethylene selectivity was in the range of 1.9–7.94 below 100kPa. Lately, Liang et al applied asphalt, a readily available byproduct from petroleum refinery, as carbon precursor to prepare a series of asphalt‐based activated carbons (A‐ACs), and reported that the A‐ACs possessed ethane‐selective characteristic, and showed superhigh ethane uptake of 7.2 mmol/g at 298 K and 100 kPa. Also, the contents of heteroatom in A‐ACs were reported to affect the ethane/ethylene adsorption.…”

“…It is, therefore, meaningful to increase the microporosity so as to enhance the utilization ratio of pore volume. Besides, the surface heteroatom contents of C‐PDAs and A‐ACs are still relatively low, so introducing more heteroatoms on the adsorbents was considered as a feasible method to improve the ethane/ethylene adsorptive separation. Therefore, developing microporous activated carbon with appropriate surface chemistry may contribute to an effective ethane‐selective adsorbent for ethane/ethylene separation from cracked gas.…”