What is a common feature of pressure swing absorption technology?

Pressure swing absorption (PSA) technology is primarily used for the selective removal of certain gases from a mixture, which is a fundamental component of the process. In PSA systems, gases are passed through adsorbent materials that preferentially take up specific molecules, effectively filtering out unwanted components based on their physical or chemical properties. This allows for the separation and purification of target gases, such as oxygen or nitrogen, from the surrounding mixture.

The selective filtration aspect is crucial because it enables the system to operate efficiently and effectively by targeting specific gases while letting others pass through. This is important for applications such as producing high-purity oxygen for diving or medical use. Understanding the role of selective filtration helps divers and operators to choose the right gas mixtures for different activities, particularly in ensuring safety and efficiency during dives.

The other options related to direct cooling, vacuum creation, and gas compression do not describe the key operational feature of PSA technology, which focuses on the process of filtering and selectively absorbing gases rather than manipulating them through these other methods.