Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases
Impregnated activated carbons (IACs) used in air filtration gradually lose their efficacy for the chemisorption of noxious gases when exposed to humidity due to impregnated metal deactivation. In order to stabilize IACs against aging, and to prolong the filters’ shelf life, inorganic phosphate compo...
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| Format: | Article |
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MDPI AG
2023-08-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/24/16/13000 |
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| author | Ido Nir Vladislav Shepelev Alexander Pevzner Daniele Marciano Lilach Rosh Tal Amitay-Rosen Hadar Rotter |
| author_facet | Ido Nir Vladislav Shepelev Alexander Pevzner Daniele Marciano Lilach Rosh Tal Amitay-Rosen Hadar Rotter |
| author_sort | Ido Nir |
| collection | DOAJ |
| description | Impregnated activated carbons (IACs) used in air filtration gradually lose their efficacy for the chemisorption of noxious gases when exposed to humidity due to impregnated metal deactivation. In order to stabilize IACs against aging, and to prolong the filters’ shelf life, inorganic phosphate compounds (phosphoric acid and its three salts, NaHPO<sub>4</sub>, Na<sub>2</sub>HPO<sub>4</sub>, and Na<sub>3</sub>PO<sub>4</sub>) were used as anti-aging additives for two different chromium-free IACs impregnated with copper, zinc, molybdenum, and triethylenediamine (TEDA). Phosphoric acid, monosodium, and disodium phosphate were found to be very efficient in inhibiting the aging of IACs over long periods against cyanogen chloride (the test agent) chemisorption, with the latter being the most efficient. However, the efficiency of phosphate as an anti-aging additive was not well correlated with its ability to inhibit the migration of metal impregnants, especially copper, from the interior to the external surface of carbon granules. Unlike organic additives, the inorganic phosphate additives did not decrease the surface area of the IAC or its physical adsorption capacity for toluene. Using a phosphate additive in IAC used in collective protection and personal filters can improve the safety of the user and the environment and dramatically reduce the need to replace these filters after exposure to humid environments. This has safety, economic, logistical, and environmental advantages. |
| first_indexed | 2024-03-10T23:51:28Z |
| format | Article |
| id | doaj.art-739285178d5e443a9c8723121b7429b1 |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-10T23:51:28Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-739285178d5e443a9c8723121b7429b12023-11-19T01:33:53ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672023-08-0124161300010.3390/ijms241613000Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous GasesIdo Nir0Vladislav Shepelev1Alexander Pevzner2Daniele Marciano3Lilach Rosh4Tal Amitay-Rosen5Hadar Rotter6Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, IsraelLife Science Research Israel Ltd. (LSRI), P.O. Box 19, Ness Ziona 74100, IsraelDepartment of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, IsraelDepartment of Organic Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, IsraelDepartment of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, IsraelDepartment of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, IsraelDepartment of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, IsraelImpregnated activated carbons (IACs) used in air filtration gradually lose their efficacy for the chemisorption of noxious gases when exposed to humidity due to impregnated metal deactivation. In order to stabilize IACs against aging, and to prolong the filters’ shelf life, inorganic phosphate compounds (phosphoric acid and its three salts, NaHPO<sub>4</sub>, Na<sub>2</sub>HPO<sub>4</sub>, and Na<sub>3</sub>PO<sub>4</sub>) were used as anti-aging additives for two different chromium-free IACs impregnated with copper, zinc, molybdenum, and triethylenediamine (TEDA). Phosphoric acid, monosodium, and disodium phosphate were found to be very efficient in inhibiting the aging of IACs over long periods against cyanogen chloride (the test agent) chemisorption, with the latter being the most efficient. However, the efficiency of phosphate as an anti-aging additive was not well correlated with its ability to inhibit the migration of metal impregnants, especially copper, from the interior to the external surface of carbon granules. Unlike organic additives, the inorganic phosphate additives did not decrease the surface area of the IAC or its physical adsorption capacity for toluene. Using a phosphate additive in IAC used in collective protection and personal filters can improve the safety of the user and the environment and dramatically reduce the need to replace these filters after exposure to humid environments. This has safety, economic, logistical, and environmental advantages.https://www.mdpi.com/1422-0067/24/16/13000agingactivated carboncyanogen chloridephosphateimpregnationadsorption |
| spellingShingle | Ido Nir Vladislav Shepelev Alexander Pevzner Daniele Marciano Lilach Rosh Tal Amitay-Rosen Hadar Rotter Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases International Journal of Molecular Sciences aging activated carbon cyanogen chloride phosphate impregnation adsorption |
| title | Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases |
| title_full | Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases |
| title_fullStr | Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases |
| title_full_unstemmed | Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases |
| title_short | Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases |
| title_sort | phosphate additives for aging inhibition of impregnated activated carbon against hazardous gases |
| topic | aging activated carbon cyanogen chloride phosphate impregnation adsorption |
| url | https://www.mdpi.com/1422-0067/24/16/13000 |
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