Chitosan-Derived Porous Activated Carbon for the Removal of the Chemical Warfare Agent Simulant Dimethyl Methylphosphonate

Methods for the rapid removal of chemical warfare agents are of critical importance. In this work, a porous activated carbon material (C-PAC) was prepared from chitosan flakes via single-step potassium carbonate (K2CO3) activation for the prompt adsorption of dimethyl methylphosphonate (DMMP). C-PAC samples were prepared using different carbonization temperatures (350, 550, and 750 °C) at a constant K2CO3/chitosan ratio (1:2) and using different activator ratios (K2CO3/chitosan ratios of 1:0.5, 1:1, 1:2, and 1:3) at 750 °C. Furthermore, we evaluated the effect of preparation conditions on the adsorption capacities of the various C-PAC materials for DMMP under ambient conditions (25 °C). Notably, for the C-PAC material prepared at 750 °C using a K2CO3/chitosan ratio of 1:2, the DMMP adsorption was saturated at approximately 412 mg·g−1 carbon after 48 h. The good performance of this material makes it a potential candidate for use in remedial applications or protective gear.

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Acid is a potential interferent in fluorescent sensing of chemical warfare agent vapors

Communications Chemistry ◽

10.1038/s42004-021-00482-6 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Shengqiang Fan ◽

Genevieve H. Dennison ◽

Nicholas FitzGerald ◽

Paul L. Burn ◽

Ian R. Gentle ◽

...

Keyword(s):

Chemical Warfare Agents ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Standard Laboratory ◽

Care Needs ◽

Fluorescent Sensing ◽

Sensing Systems ◽

Sensing Material ◽

Fluorescence Change ◽

Warfare Agents

AbstractA common feature of fluorescent sensing materials for detecting chemical warfare agents (CWAs) and simulants is the presence of nitrogen-based groups designed to nucleophilically displace a phosphorus atom substituent, with the reaction causing a measurable fluorescence change. However, such groups are also basic and so sensitive to acid. In this study we show it is critical to disentangle the response of a candidate sensing material to acid and CWA simulant. We report that pyridyl-containing sensing materials designed to react with a CWA gave a strong and rapid increase in fluorescence when exposed to Sarin, which is known to contain hydrofluoric acid. However, when tested against acid-free diethylchlorophosphate and di-iso-propylfluorophosphate, simulants typically used for evaluating novel G-series CWA sensors, there was no change in the fluorescence. In contrast, simulants that had been stored or tested under a standard laboratory conditions all led to strong changes in fluorescence, due to acid impurities. Thus the results provide strong evidence that care needs to be taken when interpreting the results of fluorescence-based solid-state sensing studies of G-series CWAs and their simulants. There are also implications for the application of these pyridyl-based fluorescence and other nucleophilic/basic sensing systems to real-world CWA detection.

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Modified-TiO2 Photocatalyst Supported on β-SiC Foams for the Elimination of Gaseous Diethyl Sulfide as an Analog for Chemical Warfare Agent: Towards the Development of a Photoreactor Prototype

Catalysts ◽

10.3390/catal11030403 ◽

2021 ◽

Vol 11 (3) ◽

pp. 403

Author(s):

Armelle Sengele ◽

Didier Robert ◽

Nicolas Keller ◽

Valérie Keller

Keyword(s):

Photocatalytic Oxidation ◽

Chemical Warfare Agents ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Diethyl Sulfide ◽

Tio2 Photocatalysts ◽

Doped Tio2 ◽

Model Molecule ◽

Warfare Agents ◽

Oxidation Efficiency

In the context of the increase in chemical threat due to warfare agents, the development of efficient methods for destruction of Chemical Warfare Agents (CWAs) are of first importance both for civilian and military purposes. Amongst possible methods for destruction of CWAs, photocatalytic oxidation is an alternative one. The present paper reports on the preparation of Ta and Sn doped TiO2 photocatalysts immobilized on β-SiC foams for the elimination of diethyl sulfide (DES) used as a model molecule mimicking Yperite (Mustard Gas) in gaseous phase. Photo-oxidation efficiency of doped TiO2 catalyst has been compared with TiO2-P25. Here, we demonstrate that the Sn doped-TiO2 with a Polyethylene glycol (PEG)/TiO2 ratio of 7 exhibits the best initial activity (up to 90%) but is deactivates more quickly than Ta doped-TiO2 (40% after 800 min). The activity of the catalysts is strongly influenced by the adsorption properties of the support, as β-SiC foams adsorb DES and other sulfur compounds. This adsorption makes it possible to limit the poisoning of the catalysts and to maintain an acceptable conversion rate even after ten hours under continuous DES flow. Washing with NaOH completely regenerates the catalyst after a firs treatment and even seems to “wash” it by removing impurities initially present on the foams.

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Copper supported on porous activated carbon obtained by wetness impregnation: Effect of preparation conditions on the ozonation catalyst's characteristics

Comptes Rendus Chimie ◽

10.1016/j.crci.2014.07.011 ◽

2015 ◽

Vol 18 (1) ◽

pp. 100-109 ◽

Cited By ~ 31

Author(s):

Asma Abdedayem ◽

Monia Guiza ◽

Abdelmottaleb Ouederni

Keyword(s):

Activated Carbon ◽

Preparation Conditions ◽

Porous Activated Carbon

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Effects of incorporating regioisomers and flexible rotors to direct aggregation induced emission to achieve stimuli-responsive luminogens, security inks and chemical warfare agent sensors

Chemical Communications ◽

10.1039/d0cc02318c ◽

2020 ◽

Vol 56 (55) ◽

pp. 7633-7636 ◽

Cited By ~ 3

Author(s):

Laxmi Raman Adil ◽

Parameswar Krishnan Iyer

Keyword(s):

Photophysical Properties ◽

Chemical Warfare Agents ◽

Design Strategy ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Simple Design ◽

Stimuli Responsive ◽

Aggregation Induced Emission ◽

Flexible Rotors ◽

Warfare Agents

A simple design strategy to convert ACQ materials into bright AIE luminogens is demonstrated. Unique differences in photophysical properties were observed among them which gave rise to stimuli responsive behaviour and sensor for chemical warfare agents.

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Vapor Selectivity of a Natural Photonic Crystal to Binary and Tertiary Mixtures Containing Chemical Warfare Agent Simulants

Sensors ◽

10.3390/s20010157 ◽

2019 ◽

Vol 20 (1) ◽

pp. 157 ◽

Cited By ~ 4

Author(s):

Joshua Kittle ◽

Benjamin Fisher ◽

Courtney Kunselman ◽

Aimee Morey ◽

Andrea Abel

Keyword(s):

Photonic Crystals ◽

Chemical Warfare Agent ◽

Nerve Agent ◽

Chemical Warfare ◽

Mustard Gas ◽

Dimethyl Methylphosphonate ◽

Vapor Sensing ◽

Sensitivity Level ◽

Vapor Mixtures ◽

Wing Scales

Vapor sensing via light reflected from photonic crystals has been increasingly studied as a means to rapidly identify analytes, though few studies have characterized vapor mixtures or chemical warfare agent simulants via this technique. In this work, light reflected from the natural photonic crystals found within the wing scales of the Morpho didius butterfly was analyzed after exposure to binary and tertiary mixtures containing dimethyl methylphosphonate, a nerve agent simulant, and dichloropentane, a mustard gas simulant. Distinguishable spectra were generated with concentrations tested as low as 30 ppm and 60 ppm for dimethyl methylphosphonate and dichloropentane, respectively. Individual vapors, as well as mixtures, yielded unique responses over a range of concentrations, though the response of binary and tertiary mixtures was not always found to be additive. Thus, while selective and sensitive to vapor mixtures containing chemical warfare agent simulants, this technique presents challenges to identifying these simulants at a sensitivity level appropriate for their toxicity.

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Synergism of Activated Carbon and Undoped and Nitrogen-doped TiO2in the Photocatalytic Degradation of the Chemical Warfare Agents Soman, VX, and Yperite

ChemSusChem ◽

10.1002/cssc.200800246 ◽

2009 ◽

Vol 2 (5) ◽

pp. 427-436 ◽

Cited By ~ 26

Author(s):

Bogdan Cojocaru ◽

Ştefan Neaţu ◽

Vasile I. Pârvulescu ◽

Vasile Şomoghi ◽

Nicoleta Petrea ◽

...

Keyword(s):

Activated Carbon ◽

Photocatalytic Degradation ◽

Chemical Warfare Agents ◽

Chemical Warfare ◽

Nitrogen Doped ◽

Warfare Agents

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Ion Mobility Spectrometry for Monitoring Chemical Warfare Agents

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.241-244.980 ◽

2012 ◽

Vol 241-244 ◽

pp. 980-983 ◽

Cited By ~ 2

Author(s):

Jian Zheng ◽

Tian Min Shu ◽

Jie Jin

Keyword(s):

Ion Mobility Spectrometry ◽

Ion Mobility ◽

Cluster Formation ◽

Chemical Warfare Agents ◽

Chemical Warfare ◽

Ambient Conditions ◽

Ionization Source ◽

Warfare Agents ◽

Positive Mode ◽

Detecting Method

The technique of ion mobility spectrometry (IMS) offers a practical and fast detecting method in ambient conditions to estimate whether there may presence contrabands or even chemical warfare agents (CWAs). In this work we have investigated a self-made radioactive 63Ni (β emission) ionization source for ion mobility spectrometry employed with an atmospheric pressure to detect real CWAs, such as GB, GD, HD, VX from aerosol samples. Furthermore, we have experimentally studied the influence of drift tube temperature not only in ion cluster formation in the positive mode, but also the detection limitation of CWAs.

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Detection of organophosphorus compounds using a surface acoustic wave array sensor based on supramolecular self-assembling imprinted films

Analytical Methods ◽

10.1039/d0ay00211a ◽

2020 ◽

Vol 12 (17) ◽

pp. 2206-2214 ◽

Cited By ~ 1

Author(s):

Yong Pan ◽

Tengxiao Guo ◽

Genwei Zhang ◽

Junchao Yang ◽

Liu Yang ◽

...

Keyword(s):

Acoustic Wave ◽

Surface Acoustic Wave ◽

Tributyl Phosphate ◽

Organophosphorus Compounds ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Dimethyl Methylphosphonate ◽

Array Sensor ◽

Self Assembling

In this study, diisopropyl methylphosphonate (DIMP), tributyl phosphate (TBP), and dimethyl methylphosphonate (DMMP) were selected as organophosphorus chemical warfare agent (CWA) simulants.

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The ionization process of chemical warfare agent simulants in low temperature plasma ionization

European Journal of Mass Spectrometry ◽

10.1177/1469066720951943 ◽

2020 ◽

Vol 26 (5) ◽

pp. 341-350

Author(s):

Baoqiang Li ◽

Jinglin Kong ◽

Lin Zhang ◽

Wenxiang Fu ◽

Zhongyao Zhang ◽

...

Keyword(s):

Low Temperature ◽

Chemical Warfare Agents ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Collision Induced Dissociation ◽

Low Temperature Plasma ◽

Temperature Plasma ◽

Plasma Ionization ◽

Warfare Agents ◽

Protonated Molecules

The application of low-temperature plasma ionization technology in the chemical warfare agent detection was mostly focused on the research of rapid detection methods. Limited studies are available on the ionization process of chemical warfare agents in low temperature plasma. Through the intensity of protonated molecules of dimethyl methylphosphonate (DMMP) in different solvents including methanol, deuterated methanol (methanol-D4), pure water, and deuterium oxide (water-D2), it was concluded that the water molecule in the air provides the hydrogen ion (H+) needed for ionization. The product ion spectra and the collision-induced dissociation processes of protonated molecules of nerve agent simulants, including DMMP, diethyl methanephosphonate (DEMP), trimethyl phosphate (TMP), triethyl phosphate (TEP), tripropyl phosphate (TPP), and tributyl phosphate (TBP) were analyzed. Results revealed that H+ mostly combined with phosphorus oxygen double bond (P = O) in the low-temperature plasma ionization. By analyzing the peak intensity distribution of product ions of protonated molecules, the presence of proton and charge migration in the low temperature plasma ionization and collision-induced dissociation were researched. This study could provide technical guidance for the rapid and accurate detection of chemical warfare agents through low temperature plasma ionization-mass spectrometry.

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