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4. All-Weather Dry Decontaminant Polymer-H2O2Complex for HD Degradation

Author

Landers, John, Wang, Hui, Mahle, John, Myers, Joseph, Nichols, Douglas, Emmons, Erik, Tripathi, Ashish, Hall, Morgan, Bruni, Eric, Peterson, Gregory W., and Karwacki, Christopher J.

Abstract

Hydrogen peroxide (H2O2) is a highly effective decontaminant against chemical warfare agents (CWAs) when present both in a liquid and as a solid powder. For the latter, this can be in the form of H2O2being complexed to a polymer, such as polyvinylpyrrolidone (PVP). While a H2O2–PVP complex is indeed effective at decontaminating CWAs, it is vulnerable to environmental conditions such as high relative humidities (RH), which can dissociate the H2O2from the complex before it is given the opportunity to react with CWAs. In this paper, we demonstrate that the cross-linked version of PVP forms a highly stable complex with H2O2, which can withstand both high (40 °C) and low (−20 °C) temperatures as well as maintain stability at high RH up to 90% over several days. Collectively, this lays the framework for processing the H2O2–PVP complex in a variety of form factors that can maintain efficacy under a wide range of real-world environmental conditions.

Published
2024
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10. In Situ Nuclear Magnetic Resonance Investigation of Molecular Adsorption and Kinetics in Metal–Organic Framework UiO-66

Author

An, Yao, primary, Kleinhammes, Alfred, additional, Doyle, Patrick, additional, Chen, En-Yi, additional, Song, Yan, additional, Morris, Amanda J., additional, Gibbons, Bradley, additional, Cai, Meng, additional, Johnson, J. Karl, additional, Shukla, Priyanka B., additional, Vo, Minh Nguyen, additional, Wei, Xin, additional, Wilmer, Christopher E., additional, Ruffley, Jonathan P., additional, Huang, Liangliang, additional, Tovar, Trenton M., additional, Mahle, John J., additional, Karwacki, Christopher J., additional, and Wu, Yue, additional

Published
2021
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11. Modeling of Diffusion of Acetone in UiO-66

Author

Wardzala, Jacob J., primary, Ruffley, Jonathan P., additional, Goodenough, Isabella, additional, Schmidt, Allie M., additional, Shukla, Priyanka B., additional, Wei, Xin, additional, Bagusetty, Abhishek, additional, De Souza, Mattheus, additional, Das, Prasenjit, additional, Thompson, Dorian J., additional, Karwacki, Christopher J., additional, Wilmer, Christopher E., additional, Borguet, Eric, additional, Rosi, Nathaniel L., additional, and Johnson, J. Karl, additional

Published
2020
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14. Metal–Organic Framework- and Polyoxometalate-Based Sorbents for the Uptake and Destruction of Chemical Warfare Agents

Author

Grissom, Tyler G., primary, Plonka, Anna M., additional, Sharp, Conor H., additional, Ebrahim, Amani M., additional, Tian, Yiyao, additional, Collins-Wildman, Daniel L., additional, Kaledin, Alexey L., additional, Siegal, Harrison J., additional, Troya, Diego, additional, Hill, Craig L., additional, Frenkel, Anatoly I., additional, Musaev, Djamaladdin G., additional, Gordon, Wesley O., additional, Karwacki, Christopher J., additional, Mitchell, Mark B., additional, and Morris, John R., additional

Published
2020
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28. Optimizing Toxic Chemical Removal through Defect-Induced UiO-66-NH2 Metal-Organic Framework.

Author

Peterson, Gregory W., Destefano, Matthew R., Garibay, Sergio J., Ploskonka, Ann, McEntee, Monica, Hall, Morgan, Karwacki, Christopher J., Hupp, Joseph T., and Farha, Omar K.

Subjects
ORGANOMETALLIC compounds, HYDROLYSIS, POISONS, METAL-organic frameworks, CHEMICAL reactions
Abstract

For the first time, an increasing number of defects were introduced to the metal-organic framework UiO-66-NH2 in an attempt to understand the structure-activity trade-offs associated with toxic chemical removal. It was found that an optimum exists with moderate defects for toxic chemicals that react with the linker, whereas those that require hydrolysis at the secondary building unit performed better when more defects were introduced. The insights obtained through this work highlight the ability to dial-in appropriate material formulations, even within the same parent metal-organic framework, allowing for trade-offs between reaction efficiency and mass transfer. [ABSTRACT FROM AUTHOR]

Published
2017
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32. Ammonia Vapor Removal by Cu3(BTC)2 and Its Characterization by MAS NMR

Author

NEW YORK STRUCTURAL BIOLOGY CENTER INC NEW YORK NY, Peterson, Gregory W, Wagner, George W, Balboa, Alex, Mahle, John, Sewell, Tara, Karwacki, Christopher J, NEW YORK STRUCTURAL BIOLOGY CENTER INC NEW YORK NY, Peterson, Gregory W, Wagner, George W, Balboa, Alex, Mahle, John, Sewell, Tara, and Karwacki, Christopher J

Abstract

Adsorption equilibria and NMR experiments were performed to study the adsorption and interactions of ammonia with metal-organic framework HKUST-1, or Cu3(BTC)2 (BTC ) 1,3,5-benzenetricarboxylate). Ammonia capacities determined from chemical breakthrough measurements show significantly higher uptake capacities than from adsorption alone, suggesting a stronger interaction involving a potential reaction with the Cu3(BTC)2 framework. Indeed, 1H MAS NMR reveals that a major disruption of the relatively simple spectrum of Cu3(BTC)2 occurs to generate a composite spectrum consistent with Cu(OH)2 and (NH4)3BTC species under humid conditions--the anticipated products of a copper(II) carboxylate reacted with limited ammonia. These species are not detected under dry conditions; however, reaction stoichiometry combined with XRD results suggests the partial formation of an indeterminate diammine copper(II) complex with some residual Cu3(BTC)2 structure retained. Cu(II)-induced paramagnetic shifts exhibited by various species in 1H and 13C MAS NMR spectra are consistent with model compounds and previous literature. Although results show extensive ammonia capacity of Cu3(BTC)2, much of the capacity is due to reaction with the structure itself, causing a permanent loss in porosity and structural integrity., Published in The Journal of Physical Chemistry C, v113 n31 p13906-13917, 2009. The original document contains color images.

Published
2009

33. Evaluation of MOF-74, MOF-177, and ZIF-8 for the Removal of Toxic Industrial Chemicals

Author

EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR, Peterson, Gregory W., Mahle, John, Balboa, Alex, Wagner, George, Sewell, Tara, Karwacki, Christopher J., EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR, Peterson, Gregory W., Mahle, John, Balboa, Alex, Wagner, George, Sewell, Tara, and Karwacki, Christopher J.

Abstract

Current technology-based efforts are focusing on a nanotechnology approach to sorbent development for air purification applications. Metal-organic frameworks (MOFs) and zeolitic imidazolate frameworks (ZIFs) are two novel classes of materials that allow for specific functionalities to be designed directly into a porous framework. This report is the second in a series of summary reports based on the evaluation of samples from the University of California, Los Angeles. The samples evaluated in this report are a continuation of a baseline series of materials aimed at collecting design rules for future materials; results from this and the previous report will be used to create a second-generation of reactive MOFs and ZIFs for air purification applications. Testing of the novel materials included nitrogen isotherm data, water, and chloroethane adsorption equilibria, and ammonia, cyanogen chloride and sulfur dioxide breakthrough data., The original document contains color images. All DTIC reproductions will be in black and white.

Published
2008

34. Evaluation of Titania Nanotubes for the Removal of Toxic Industrial Chemicals

Author

EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR, Peterson, Gregory W., Wagner, George W., Mahle, John J., Balboa, Alex, Sewell, Tara L., Karwacki, Christopher J., EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR, Peterson, Gregory W., Wagner, George W., Mahle, John J., Balboa, Alex, Sewell, Tara L., and Karwacki, Christopher J.

Abstract

Current technology-based efforts are focusing on a nanotechnology approach to sorbent development for air purification applications. Titania nanotubes have recently been identified as extremely active under certain circumstances for decontamination of chemical warfare agents (CWAs). Furthermore, the possibility to add functional moieties to the nanotubes makes these materials an interesting candidate for evaluation against toxic industrial chemicals. This report summarizes the evaluation of titania nanotubes using nitrogen isotherm data, water and chloroethane adsorption - equilibria, and ammonia, cyanogen chloride (CK), and sulfur dioxide breakthrough data., Project Number BA07PRO104.

Published
2008

35. Evaluation of Metal-Organic Frameworks for the Removal of Toxic Industrial Chemicals

Author

EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD, Peterson, Gregory W., Mahle, John J., Balboa, Alex, Sewell, Tara L., Karwacki, Christopher J., Friday, David, EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD, Peterson, Gregory W., Mahle, John J., Balboa, Alex, Sewell, Tara L., Karwacki, Christopher J., and Friday, David

Abstract

Current technology-based efforts are focusing on a nanotechnology approach to sorbent development for air purification applications. Metal-organic frameworks, or MOFs, are one novel class of materials that allow for specific functionalities to be designed directly into a porous framework. This report summarizes the evaluation of four MOFs using nitrogen isotherm data, temperature stability analyses, water and chloroethane adsorption equilibria, and ammonia, cyanogen chloride (CK), and sulfur dioxide breakthrough data., The original document contains color images. All DTIC reproductions will be in black and white. Prepared in collaboration with Hunter Applied Research Center, Edgewood, MD.

Published
2008

42. Recirculation Filter Unit for the M28 Simplified Collective Protection Systems: Adsorption Equilibria of Candidate Nonwoven Microporous Media

Author

EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD, Karwacki, Christopher J., EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD, and Karwacki, Christopher J.

Abstract

Adsorption equilibria of nitrogen, hexane, and DMMP are provided on two nonwoven adsorbent materials recommended for use in the recirculation filter unit (RFU) for the M28 Collective Protection System. The objective of this report is to correlate adsorption equilibria of the three adsorbates and to provide a model to predict the adsorption capacity of the media for toxic chemical agents over an extended range of vapor concentrations. This information may be used to select the best adsorbent materials for the RFU as well as to establish production acceptance criteria consistent with field use requirements. Adsorption equilibria of nitrogen, hexane, and DMMP on POLYSORB (PS) and Purification Products (PP) adsorbent materials show that there is much less adsorption capacity per unit packing volume than typical granular bed activated carbons such as BPL. A Dubinin-Radustikevich (DR) potential plot of the combined nitrogen, hexane, and DMMP data shows that the total estimated micropore volume of the PS and PP adsorbent materials is 0.113 and 0.077 mL/g of material, respectively. On a volume basis, the PP material may provide about 2.8 times more adsorptive capacity than the PS material. The estimated adsorbed phase loading of HE) mustard at 0.029 mg/m(3) at 25 degrees C is about 0.035 and 0.015 mL/g of material for the PS and PP materials, respectively.

Published
2000

44. Compatibility of Polyvinyl Chloride Filter Bags with Chloroform Vapors.

Author

EDGEWOOD RESEARCH DEVELOPMENT AND ENGINEERING CENTER ABERDEEN PROVING GROUNDMD, Karwacki, Christopher J., EDGEWOOD RESEARCH DEVELOPMENT AND ENGINEERING CENTER ABERDEEN PROVING GROUNDMD, and Karwacki, Christopher J.

Abstract

A determination is made on the compatibility of polyvinyl chloride (PVC) filter bags when exposed to chloroform vapors resulting from offgassing of contaminated adsorbent filters. The objectives of this investigation were to estimate the concentrations of chloroform desorbed from Rapid Response System (RRS) filters previously exposed to chloroform and evaluate the compatibility of PVC sheet to chloroform vapors. The results of the investigation showed that desorption of chloroform vapors from the RRS filter can result in concentrations of approximately 0.2 to 13.0 mg/L when sealed in a closed container. The amount of desorption is primarily dependent upon the initial loading of chloroform on the adsorbent and the temperature of the filter bed. The PVC compatibility results showed that the equilibrated weight uptake on PVC sheet was 33.6 micron grams/cm2 when exposed to 10.0 mg/L vapor concentration. The results support the work of other investigators that showed significant uptake of chloroform on PVC in liquid immersion tests. Although no permeation of chloroform through PVC sheet was observed during the 10-day exposure periods the measured uptake could indicate the initial stages of long term permeation.

Published
1997

48. Adsorption of 2-Chloroethyl Ethyl Sulfide on Silica: Binding Mechanism and Energy of a Bifunctional Hydrogen-Bond Acceptor at the Gas–Surface Interface

Author

Abelard, Joshua, Wilmsmeyer, Amanda R., Edwards, Angela C., Gordon, Wesley O., Durke, Erin M., Karwacki, Christopher J., Troya, Diego, and Morris, John R.

Abstract

This work investigates the fundamental nature of sulfur mustard surface adsorption by characterizing interfacial hydrogen bonding and other intermolecular forces for the surrogate molecule (simulant) 2-chloroethyl ethyl sulfide (2-CEES). Adsorption at the surface of amorphous silica is the focus of this work because of silica’s low chemical reactivity, well-known properties, and abundance in the environment. 2-CEES has two polar functional groups, the chloro and thioether moieties, available to accept hydrogen bonds from free surface silanol groups. Diethyl sulfide and chlorobutane are also investigated to independently assess the role of the chloro and thioester functionalities in the overall adsorption mechanism and to explore the interplay between the charge transfer and electrostatic contributions to total hydrogen-bond strength. Our approach utilizes infrared spectroscopy to study specific surface–molecule interactions and temperature-programmed desorption to measure the activation energy for desorption of adsorbed molecules. Our results indicate that 2-CEES adsorbs to silica by hydrogen bonding through either the chloro or thioether moieties but is unable to form a more stable configuration in which both polar groups interact simultaneously with adjacent silanol groups. The activation energy for desorption of 2-CEES is nearly 43 kJ/mol, driven by both strong hydrogen bonding and other non-bonding interactions. A systematic study of chloroalkanes reveals that each methylene group contributes approximately 5–8 kJ/mol to the overall desorption energy.

Published
2015
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49. Ammonia Vapor Removal by Cu3(BTC)2and Its Characterization by MAS NMR

Author

Peterson, Gregory W., Wagner, George W., Balboa, Alex, Mahle, John, Sewell, Tara, and Karwacki, Christopher J.

Abstract

Adsorption equilibria and NMR experiments were performed to study the adsorption and interactions of ammonia with metal−organic framework HKUST-1, or Cu3(BTC)2(BTC = 1,3,5-benzenetricarboxylate). Ammonia capacities determined from chemical breakthrough measurements show significantly higher uptake capacities than from adsorption alone, suggesting a stronger interaction involving a potential reaction with the Cu3(BTC)2framework. Indeed, 1H MAS NMR reveals that a major disruption of the relatively simple spectrum of Cu3(BTC)2occurs to generate a composite spectrum consistent with Cu(OH)2and (NH4)3BTC species under humid conditionsthe anticipated products of a copper(II) carboxylate reacted with limited ammonia. These species are not detected under dry conditions; however, reaction stoichiometry combined with XRD results suggests the partial formation of an indeterminate diammine copper(II) complex with some residual Cu3(BTC)2structure retained. Cu(II)-induced paramagnetic shifts exhibited by various species in 1H and 13C MAS NMR spectra are consistent with model compounds and previous literature. Although results show extensive ammonia capacity of Cu3(BTC)2, much of the capacity is due to reaction with the structure itself, causing a permanent loss in porosity and structural integrity.

Published
2009
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50. All-Weather Dry Decontaminant Polymer-H 2 O 2 Complex for HD Degradation.

Author

Landers J, Wang H, Mahle J, Myers J, Nichols D, Emmons E, Tripathi A, Hall M, Bruni E, Peterson GW, and Karwacki CJ

Abstract

Hydrogen peroxide (H 2 O 2 ) is a highly effective decontaminant against chemical warfare agents (CWAs) when present both in a liquid and as a solid powder. For the latter, this can be in the form of H 2 O 2 being complexed to a polymer, such as polyvinylpyrrolidone (PVP). While a H 2 O 2 -PVP complex is indeed effective at decontaminating CWAs, it is vulnerable to environmental conditions such as high relative humidities (RH), which can dissociate the H 2 O 2 from the complex before it is given the opportunity to react with CWAs. In this paper, we demonstrate that the cross-linked version of PVP forms a highly stable complex with H 2 O 2 , which can withstand both high (40 °C) and low (-20 °C) temperatures as well as maintain stability at high RH up to 90% over several days. Collectively, this lays the framework for processing the H 2 O 2 -PVP complex in a variety of form factors that can maintain efficacy under a wide range of real-world environmental conditions.

Published
2024
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