Ethylene/Ethane Separation by Membranes

The separation of ethylene from ethane and propylene from propane is a challenging operation. It is involved in the production of light olefins, such as ethylene and propylene, which represent the most important building blocks in the petrochemical industry. Cryogenic distillation, conventionally applied to this separation, is highly energy intensive, requiring expensive tall columns, operated under low temperature and high pressure, with very high reflux ratios and requiring ethylene/propylene refrigeration systems for low-temperature cooling (Eldridge 1993).

Due to the complexity and difficulty of the separation process, mixtures including olefins produced in the petroleum and refining process are often used as fuel. Membrane separation, recognized as a low-energy method, appears the most promising among alternative separation techniques, such as extractive distillation, adsorption, and absorption, to recover these valuable compounds (Rungta et al. 2013). Polymeric membranes, cheap...