What includes methods such as molecular sieve and semipermeable plastic membrane for producing oxygen?

The method that includes techniques like molecular sieve and semipermeable plastic membrane for producing oxygen is based on physical separation principles. This method works by taking advantage of the different physical properties of gases. For instance, the molecular sieve uses materials that preferentially absorb nitrogen from the air, allowing the oxygen to pass through and be collected.

Similarly, semipermeable membranes can selectively allow oxygen to diffuse through while blocking other gases, resulting in a higher concentration of oxygen on one side. These approaches do not involve chemical reactions but rely on the physical characteristics of the gases involved, making them suitable for oxygen production in various applications, such as medical facilities and industrial processes.

In contrast, electrolysis involves using electricity to break down compounds into their constituent elements; combustion relies on chemical reactions that produce energy and various byproducts, which is not applicable to producing pure oxygen from air. Fractional distillation involves cooling gases to separate them based on their boiling points, but it does not utilize molecular sieves or membranes as the primary means of separation.