Application of Zeotype SAPO-34 Molecular Sieve as a Selective Adsorbent for Separation of Ethylene from Ethane

The process of ethylene production from ethane dehydrogenation is one of the interesting processes in the field of conversion the petroleum light gases to the valuable products. In this process, the outlet gaseous product is a combination of ethylene, ethane and hydrogen. Effective separation techniques are required for separation of ethylene from unreacted ethane. Here a new adsorbent approach is introduced for separation of ethylene from ethane. The adsorbent is a kind of zeolite- like molecular sieve from silico-alumino-phosphate group (SAPO-34) which is previously synthesized and studied in the adsorption tests of ethane and ethylene. The equilibrium adsorption experiments are performed in a static batch adsorption apparatus at various moderate pressures and room temperature to evaluate the adsorption capacity and selectivity toward ethylene against ethane. A high tendency of SAPO-34 towards ethylene and the ethylene/ethane selectivity from 2 to 3 fold in the pressure range of 200 to 800 kPa is observed, confirming the potential application of SAPO-34 as an adsorbent in the adsorption process for separation of ethylene and ethane.