Avoiding Cross Contamination
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Selectivity:
Molecular Sieve 3Å (Ecosorb 300) coated / used on the aluminum substrate. This is recommended where there is a need to limit the cross contamination to absolute minimum and ensure exclusion of contaminants in the air streams while transferring water vapor molecules.
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Variations In Pore Diameter Among Dessants
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Relative Particl Size
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| Relative Sizes Of Various Materials In Angstroms |
| ITEM |
SIZE (Å) |
| Hair |
15000 |
| Bacteria |
340-10000 |
| Viruses |
160-270 |
| Chloroform |
6.9 |
| Toluene |
6.7 |
| Propylene |
5.0 |
| Ethanol |
4.4 |
| Methane |
4.0 |
| Ammonia |
3.6 |
| Water |
2.8 |
| Oxygen |
2.8 |
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| Critical Diameters of Various Molecules |
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All Diameters Expressed In Ångstrom Units
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| Helium |
2.0 |
| Hydrogen, acetylene |
2.4 |
| Water, Oxygen, Carbon, Monoxide, Carbon Dioxide |
2.8 |
| Nitrogen |
3.0 |
| Ammonia, Hydrogen Sulfide |
3.6 |
| Argon |
3.8 |
| Methane |
4.0 |
| Ethylene, Ethylene Monoxide |
4.0 |
| Ethane, Methanol, Ethanol |
4.4 |
| Methyl-mercaptan |
4.5 |
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| Propane, nC4 to nC22 |
4.9 |
| Propylene |
5.0 |
| Ethyl-mercaptan, butene1, butene 2 trans |
5.1 |
| Diflurochloromethane (R 22) |
5.3 |
| Iso C22 |
5.6 |
| Cyclohexane |
6.1 |
| Toluene, paraxylene |
6.7 |
| Benzene |
6.8 |
| Carbon tetrachloride |
6.9 |
| Methaxylene |
7.1 |
| Tri-ethylamine |
8.4 |
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The possibility of adsorption depends not only on the dimension and the shape of the molecules (linear, ramified, cyclic...) but also on their polarity.
If there is no steric hindrance the molecules are preferentially adsorbed when their polarity is well pronounced. |
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| High Diffusion Rates: |
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Molecular Sieve 3Å (Ecosorb 300) coated/ used on the aluminum substrate. This allows for higher diffusion rate and slightly improved latent recovery without substantially sacrificing cross contamination. |
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| Structural Rigidity: |
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Ecofresh wheels have a extremely high structural strength as a result of the state- of- the- art winding technology and adhesives. |
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In- built purge sector eliminates cross contamination:
Purge section provides strict separation of air flows preventing carryover of dust and pollutants from exhaust air to supply air. Purge section and labyrinth sealing system limit cross contamination to .04% of the exhaust air concentration by volume.
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| Cross Contamination |
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Common Pollutants
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Molecular sieve 3Å |
Molecular sieve 4Å |
Oxidized Aluminum |
Silica Gel |
| Acetaldehyde |
0% |
>30% |
>50% |
>50% |
| Acetic Acid |
0% |
30% - 50% |
>50% |
>50% |
| Acetone |
0% |
<10% |
10% - 30% |
10% - 30% |
| Amyl Alcohol |
0% |
0% |
30% - 50% |
30% - 50% |
| Benzene |
0% |
0% |
10% - 30% |
10% - 30% |
| Butanol |
0% |
10% - 30% |
30% - 50% |
30% - 50% |
| Butylacetate |
0% |
<10% |
10% - 30% |
10% - 30% |
| ButryicAcid |
0% |
0% |
>50% |
>50% |
| Carbon Dioxide |
0% |
1% |
1% - 20% |
1% - 20% |
| Chloroform |
0% |
0% |
30% - 50% |
30% - 50% |
| Cyclohexane |
0% |
0% |
<10% |
<10% |
| Dichlorobenzene |
0% |
0% |
<10% |
<10% |
| Dioxane |
0% |
30% - 50% |
>50% |
>50% |
| Ethanol |
0% |
30% - 50% |
30% - 50% |
30% - 50% |
| Ethyl Acetate |
0% |
0% |
10% - 30% |
10% - 30% |
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