Ethylene/ethane separation by CuCl/AC adsorbent prepared using CuCl2 as a precursor

Activated carbon (AC) supported CuCl (CuCl/AC) for ethylene/ethane separation has been prepared with CuCl2 as precursor by a solid-state dispersion method. The samples are characterized by inductively coupled plasma optical emission spectrometry, X-ray diffraction, N-2 adsorption/desorption and X-ray photoelectron spectroscopy, and investigated for ethylene (C2H4) and ethane (C2H6) adsorptions. The characterization results reveal that CuCl2 supported on AC can be highly dispersed on the surfaces of AC support and completely converted to CuCl after activation at 543 K in N-2. The resultant adsorbent displays high ethylene adsorption capacity, high C2H4/C2H6 adsorption selectivity and excellent reversibility. The adsorption isotherms of ethylene and ethane on CuCl/AC at temperatures up to 333 K can be well fitted by the Sips models, and the corresponding isosteric heats of adsorption are calculated from the Clausius-Clapeyron equation. The value of isosteric heat of adsorption suggests that the interaction of ethylene with CuCl/AC is between physisorption and chemisorption.