Adsorption–desorption experiments were performed by saturating 10 g of pelletized Na-ETS-10 (16–20 mesh) in a doubleended cylindrical quartz column. The adsorbent bed height was
3.75 cm and its diameter was 2.9 cm. The sample was activated at
200 1C in a laboratory oven for 16 h under 120 mL/min helium gas
flow. During adsorption, feed gas flow was maintained at 22 1C
and 101.325 kPa. Feed gas consisted of either 59% C2H4/ 41% C2H6
mixture or 10% CO2/ 90% CH4. The feed gas mixtures were
introduced to the fixed bed adsorbent column at a flow rate of
180 mL/min (C2H4/C2H6) and 300 mL/min (CO2/CH4). The feed
gases (Praxair) were surrogate mixtures for the process gas
streams of ethylene cracking and natural gas purification units.
Outlet gas was sampled using 5 mL syringe at 5 min intervals.
Outlet gas composition was analyzed using a 5890 A Agilent Gas
Chromatograph (GC) equipped with thermal conductivity detector (TCD) and a Supelco matrix Haysep Q column (well suited for
hydrocarbon analysis). 0.5 mL samples were pulse injected and
analyzed with the GC–TCD. A continuous flow of feed gas was
maintained until the outlet composition became the same as the
inlet composition which occurred after approximately 16 min for
C2H4/C2H6 mixture and 90 min for CO2/CH4 mixture.