{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T18:41:24Z","timestamp":1773945684222,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,20]],"date-time":"2023-08-20T00:00:00Z","timestamp":1692489600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>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\u2019 shelf life, inorganic phosphate compounds (phosphoric acid and its three salts, NaHPO4, Na2HPO4, and Na3PO4) 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.<\/jats:p>","DOI":"10.3390\/ijms241613000","type":"journal-article","created":{"date-parts":[[2023,8,21]],"date-time":"2023-08-21T01:33:11Z","timestamp":1692581591000},"page":"13000","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Phosphate Additives for Aging Inhibition of Impregnated Activated Carbon against Hazardous Gases"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5112-3949","authenticated-orcid":false,"given":"Ido","family":"Nir","sequence":"first","affiliation":[{"name":"Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vladislav","family":"Shepelev","sequence":"additional","affiliation":[{"name":"Life Science Research Israel Ltd. (LSRI), P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1765-628X","authenticated-orcid":false,"given":"Alexander","family":"Pevzner","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniele","family":"Marciano","sequence":"additional","affiliation":[{"name":"Department of Organic Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lilach","family":"Rosh","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tal","family":"Amitay-Rosen","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0222-0387","authenticated-orcid":false,"given":"Hadar","family":"Rotter","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/S1573-4285(06)80012-8","article-title":"Chapter 3 Characterization of Nanoporous Carbons by Using Gas Adsorption Isotherms","volume":"Volume 7","author":"Choma","year":"2006","journal-title":"Activated Carbon Surfaces in Environmental Remediation"},{"key":"ref_2","unstructured":"Wilson, R.E., and Whetzwl, J.C. (1924). Imtrgmated Carbon and Process of Making Same. (1,519,740), U.S. Patent, Available online: https:\/\/patentimages.storage.googleapis.com\/92\/7d\/ec\/0f7014889caf4a\/US1519470.pdf."},{"key":"ref_3","unstructured":"Noyes, W.A., and Chief, J.R. (1946). Military Problems with Aerosols and Non-Persistent Gases, NDRC. Summary Technical Report of the National Defence Research Committee (NDRC), Division 10."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1016\/S1573-4285(06)80019-0","article-title":"Chapter 10 Adsorption of Chemical Warfare Agents","volume":"Volume 7","author":"Lodewyckx","year":"2006","journal-title":"Activated Carbon Surfaces in Environmental Remediation"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"60477","DOI":"10.1007\/s11356-021-15973-1","article-title":"Impregnation on Activated Carbon for Removal of Chemical Warfare Agents (CWAs) and Radioactive Content","volume":"28","author":"Kiani","year":"2021","journal-title":"Environ. Sci. Pollut. Res."},{"key":"ref_6","unstructured":"Doughty, D.T., Knebel, W.J., and Cobes, J.W. (1993). Chromium-Free Impregnated Activated Universal Respirator Carbon for Adsorption of Toxic Gases and\/or Vapors. (0 405 404 B1), EP. Patent, Available online: https:\/\/patentimages.storage.googleapis.com\/b8\/cd\/d2\/29c054f5b3f50a\/EP0405404B1.pdf."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"108797","DOI":"10.1016\/j.jece.2022.108797","article-title":"H2S Gas Adsorption Study Using Copper Impregnated on KOH Activated Carbon from Coffee Residue for Indoor Air Purification","volume":"10","author":"Wang","year":"2022","journal-title":"J. Environ. Chem. Eng."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Zulkefli, N.N., Mathuray Veeran, L.S., Noor Azam, A.M.I., Masdar, M.S., and Wan Isahak, W.N.R. (2022). Effect of Bimetallic-Activated Carbon Impregnation on Adsorption\u2013Desorption Performance for Hydrogen Sulfide (H2S) Capture. Materials, 15.","DOI":"10.3390\/ma15155409"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"57108","DOI":"10.1039\/C6RA06365A","article-title":"Coupling Catalytic Hydrolysis and Oxidation on Metal-Modified Activated Carbon for HCN Removal","volume":"6","author":"Wang","year":"2016","journal-title":"RSC Adv."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1016\/j.jhazmat.2012.07.061","article-title":"The Effect of Co-Impregnated Acids on the Performance of Zn-Based Broad Spectrum Respirator Carbons","volume":"235\u2013236","author":"Smith","year":"2012","journal-title":"J. Hazard. Mater."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1016\/0008-6223(93)90123-R","article-title":"The Effects of Molybdenum on Stabilizing the Performance of an Experimental Copper\/Zinc Impregnated, Activated Carbon","volume":"31","author":"Rossin","year":"1993","journal-title":"Carbon"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"887","DOI":"10.1016\/0008-6223(91)90164-E","article-title":"Spectroscopic Analysis and Performance of an Experimental Copper\/Zinc Impregnated, Activated Carbon","volume":"29","author":"Rossin","year":"1991","journal-title":"Carbon"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/0008-6223(91)90070-Y","article-title":"Effects of Environnental Weathering on the Properties of ASC-Whetlerite","volume":"29","author":"Rossin","year":"1991","journal-title":"Carbon"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1016\/0021-9517(86)90109-0","article-title":"Aging of Cupric Oxide Supported on Activated Carbon","volume":"100","author":"Ehrburger","year":"1986","journal-title":"J. Catal."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1016\/0008-6223(89)90032-8","article-title":"Effect of Ageing and Moisture on the Retention of Hydrogen Cyanide by Impregnated Activated Charcoals","volume":"27","author":"Brown","year":"1989","journal-title":"Carbon"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1181","DOI":"10.1016\/j.cep.2005.03.003","article-title":"Synthetic Activated Carbons for the Removal of Hydrogen Cyanide from Air","volume":"44","author":"Oliver","year":"2005","journal-title":"Chem. Eng. Process. Process Intensif."},{"key":"ref_17","unstructured":"Bischof, R., and Venetz, F. (2020). Impregnated Filter Material. (10,625,104 B2), U.S. Patent."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1016\/0008-6223(87)90120-5","article-title":"Destruction of Cyanogen Chloride with 4 Pyridine Carboxylic Acid Impregnated Activated Carbon-I. The Physical-Chemistry of Interaction","volume":"25","author":"Lahaye","year":"1987","journal-title":"Carbon"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1016\/0008-6223(93)90179-E","article-title":"Influence of Acetoacetamide on the Chemisorption of Cyano-Containing Vapors by Whetlerites","volume":"31","author":"Deitz","year":"1993","journal-title":"Carbon"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"703","DOI":"10.1016\/0008-6223(94)90092-2","article-title":"Chemisorption of Cyano-Containing Vapors by Metal-Ligand Structures Adsorbed by Activated Carbon","volume":"32","author":"Deitz","year":"1994","journal-title":"Carbon"},{"key":"ref_21","first-page":"35","article-title":"Aging of the ASC Whetlerite Type Gas Mask Carbons during Storage and Operation-Overview","volume":"3","author":"Manoilova","year":"2019","journal-title":"Secur. Futur."},{"key":"ref_22","unstructured":"Rossin, J.A. (2023, April 24). X-ray Photoelectron Spectroscopy Surface Studies of Activated Carbon. Available online: https:\/\/apps.dtic.mil\/sti\/citations\/ADA209393."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"20083","DOI":"10.1021\/jp106730j","article-title":"Role of TEDA as an Activated Carbon Impregnant for the Removal of Cyanogen Chloride from Air Streams: Synergistic Effect with Cu(Ii)","volume":"114","author":"Mahle","year":"2010","journal-title":"J. Phys. Chem. C"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"843","DOI":"10.1007\/BF02866346","article-title":"Phosphate Coordination in Copper(II) Complexes","volume":"93","author":"Sastry","year":"1984","journal-title":"Proc. Indian Acad. Sci. (Chem. Sci.)"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1007\/BF00647007","article-title":"Copper(II) Oxide Solubility Behavior in Aqueous Sodium Phosphate Solutions at Elevated Temperatures","volume":"21","author":"Ziemniak","year":"1992","journal-title":"J. Solut. Chem."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2330","DOI":"10.1021\/ic00311a017","article-title":"Hydrolysis of Phosphate Triesters with Copper(II) Catalysts","volume":"28","author":"Morrow","year":"1989","journal-title":"Inorg. Chem."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"e202200084","DOI":"10.1002\/tcr.202200084","article-title":"Hollow Structured Transition Metal Phosphates and Their Applications","volume":"22","author":"Munkaila","year":"2022","journal-title":"Chem. Record."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1021\/cm9602712","article-title":"Surface and Bulk Measurements of Metals Deposited on Activated Carbon","volume":"9","author":"Park","year":"1997","journal-title":"Chem. Mater."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1016\/j.jcis.2009.05.048","article-title":"Understanding the Role of Each Ingredient in a Basic Copper Carbonate Based Impregnation Recipe for Respirator Carbons","volume":"337","author":"Smith","year":"2009","journal-title":"J. Colloid Interface Sci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1016\/j.jcis.2011.08.031","article-title":"The Effect of Heating Temperature and Nitric Acid Treatments on the Performance of Cu- and Zn-Based Broad Spectrum Respirator Carbons","volume":"364","author":"Smith","year":"2011","journal-title":"J. Colloid Interface Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1016\/S1359-4311(00)00072-7","article-title":"Design of Packed Bed Reactors: Guides to Catalyst Shape, Size, and Loading Selection","volume":"21","author":"Afandizadeh","year":"2001","journal-title":"Appl. Therm. Eng."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/24\/16\/13000\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:38:03Z","timestamp":1760128683000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/24\/16\/13000"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,8,20]]},"references-count":31,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2023,8]]}},"alternative-id":["ijms241613000"],"URL":"https:\/\/doi.org\/10.3390\/ijms241613000","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,8,20]]}}}