Characteristics of Molecular Sieve Used in PSA Oxygen Production Systems

The molecular sieve powder used in the PSA oxygen production system is an artificially synthesized crystalline aluminosilicate.

Understanding of PSA molecular sieve

PSA molecular sieve is used in the oxygen generation process of air separation and oxygen/nitrogen separation. Compared with ordinary calcium-type and sodium-type oxygen production molecular sieves, pressure swing adsorption is suitable for various VPSA devices and has better processing capacity and separation efficiency.

In fact, there are not only one type of molecular sieve, and there are many types. At present, the main types commonly used are three categories: A-type, X-type, and Y-type. Each category has different pore sizes and properties according to different cations. Derived more subtypes, such as 3A, 4A, 5A, 10X, 13X and other models.

Characteristics of PSA molecular sieve

The pore volume of the molecular sieve accounts for about 50% of the volume, and the average internal surface area per gram of molecular sieve is 700-800m2. The oxygen production adsorption process occurs inside the pore, which can suck specific molecules smaller than the pore into the hole, and block molecules larger than the pore outside, playing the role of screening. Materials with porous structures are far more than zeolite molecular sieves. The main reason for choosing zeolite molecular sieves to participate in PSA oxygen production is that the PSA molecular sieve has the following characteristics:

• PSA molecular sieve has strong adsorption force and good selective adsorption performance.

• PSA molecular sieve has a large adsorption capacity. The amount of oxygen produced at the same flow rate and purity will be relatively small.

• PSA molecular sieve is easy to analyze and regenerate.

• PSA molecular sieve has good stability and can maintain normal adsorption capacity below 200°C.

• The PSA molecular sieve also has a relatively long service life. It can work continuously for 5-8 years under normal conditions.

Since PSA oxygen production belongs to normal temperature oxygen production in the air separation field, 5A and 13X molecular sieves are generally used.