cmSORB HP is a carbon molecular sieve (CMS): a nonpolar, carbon-based adsorbent supplied as pellets, with micropores sized close to the oxygen and nitrogen molecules. It separates the two gases by rate rather than by capacity. Oxygen typically diffuses into the pores much faster than nitrogen, so during the pressurized step of a pressure swing adsorption (PSA) cycle the bed takes up oxygen, along with water vapor and carbon dioxide, while nitrogen passes through as product gas. When the pressure drops, the adsorbed gases release and the bed is ready for the next cycle.
TYPICAL APPLICATIONS
cmSORB HP is designed for PSA nitrogen generators. The nitrogen they produce is typically used in:
- Heat treatment of metals
- Electronics manufacturing
- Food preservation
- Plastics and fiber processing
- Petrochemical processing
SIZES AND PACKAGING
- cmSORB HP pellets, grade CMSHP1-1012P, 1.0 to 1.2 mm in diameter
Supplied in 20 kg (44 lb) polyethylene drums. Bulk quantities are quoted on request.
FREQUENTLY ASKED QUESTIONS
What is carbon molecular sieve?
Carbon molecular sieve (CMS) is a carbon-based adsorbent with very narrow micropores, used mainly to produce nitrogen from compressed air in PSA generators. It is related to activated carbon in composition, but its pores are narrowed to the scale of small gas molecules, so it separates gases by how quickly each one enters the pores. Zeolite molecular sieves are a different class: crystalline aluminosilicates that separate mainly by molecular size and polarity.
How does carbon molecular sieve produce nitrogen?
A PSA nitrogen generator typically runs two beds of CMS in alternation. While one bed is pressurized with compressed air, oxygen loads into its pores and nitrogen flows out as product; before nitrogen has time to load, the generator switches beds and vents the first, releasing the oxygen. The cycle timing is what makes the separation work, so purity and output depend on how the generator is set up as much as on the sieve.
Is carbon molecular sieve used for oxygen generation?
Typically not. PSA oxygen generators and concentrators use a zeolite sieve that adsorbs nitrogen and lets oxygen pass, the reverse of what CMS does. Interra Global supplies JLOX oxygen molecular sieve for that service.
What nitrogen purity can cmSORB HP produce?
The cmSORB HP product data sheet lists performance at 0.8 MPa adsorption pressure for nitrogen purities from 99.5 to 99.999 percent. Higher purity costs output: the sheet puts productivity at 330 normal cubic meters of nitrogen per hour per tonne of sieve at 99.5 percent, falling to 95 at 99.999 percent, while the air needed per unit of nitrogen rises from 2.8 to 6.4. Figures in a given generator typically depend on its design and cycle, and Interra Global reviews service conditions when called on.
Can cmSORB HP replace the carbon molecular sieve in an existing nitrogen generator?
Generators are typically recharged with fresh sieve when a bed's output or purity falls off. Whether cmSORB HP fits a given unit typically depends on the pellet size and performance the generator was designed around; cmSORB HP pellets are 1.0 to 1.2 mm. Interra Global reviews the generator and its cycle when called on.
How should carbon molecular sieve be stored?
In a dry place, in sealed packaging. Water taken up before loading typically reduces performance, so reseal opened drums and rotate stock so the oldest material is used first. In service, the compressed air feeding a generator is typically filtered and dried before it reaches the bed, since water and oil can degrade the sieve over time.