Pressure swing adsorption for oxygen production: Adsorbents, reactors, processes and perspective

Oxygen, comprising 21% of the Earth's atmosphere, is an essential industrial gas with a wide range of applications in medical, chemical, and manufacturing industries. Pressure swing adsorption (PSA) is one of the most competitive methods for oxygen production, particularly in small and medium-scale scenarios. However, the performance of PSA is heavily influenced by adsorbents, adsorbers, and the applied process. This work presents a state-of-the-art PSA technology for oxygen production, especially focusing on recent advances in this research field. Adsorbents, commercialized and R&D, are first discussed and compared. N2/O2 selectivity ratios of the N2 selective adsorbents can be up to 26.95. The summarization then delves into the structural design of adsorbers, which highlights innovations aimed at optimizing flow dynamics and reducing pressure drop by up to 56%, with an emphasis on computational fluid dynamics (CFD) simulations. The other adsorption working processes are presented in detail when considering energy-saving techniques. Process advancements achieve O2 purities of up to 99.1% and energy consumption as low as 0.24 kWh.Nm-3. The insights into the current challenges and future directions for optimizing PSA systems are targeted to improve oxygen production performance and energy efficiency.