Zeolites for the separation of ethylene, ethane, and ethyne

Abstract

The cost-effective separation of ethylene (C₂H₄), ethyne (C₂H₂), and ethane (C₂H₆) poses a significant challenge in the contemporary chemical industry. In contrast to the energy-intensive high-pressure cryogenic distillation process, zeolite-based adsorptive separation offers a low-energy alternative. This review provides a concise overview of recent advancements in the adsorptive separation of C₂H₄, C₂H₂, and C₂H₆ using zeolites or zeolite-based adsorbents. It commences with an examination of the industrial significance of these compounds and the associated separation challenges. Subsequently, it systematically examines the utilization of various types of zeolites with diverse cationic species in such separation processes. And then it explores how different zeolitic structures impact adsorption and separation capabilities, considering principles such as cation-π interaction, π-complexation, and steric separation concerning C₂H₄, C₂H₂, and C₂H₆ molecules. Furthermore, it discusses methods to enhance the separation performance of zeolites and zeolite-based adsorbents, encompassing structural design, modifications, and ion exchange processes. Finally, it summarizes current research trends and future directions, highlighting the potential application value of zeolitic materials in the field of C₂H₄, C₂H₂, and C₂H₆ separation and offering recommendations for further investigation.