Development of a combined experimental-simulation strategy for a deeper understanding of the capture of chemical warfare agents by filter materials under different operational conditions – SESAM

SESAM proposes to develop an approach combining innovative experimental and theoretical methodologies in order to systematically evaluate the performances of MOFs with respect to the capture of chemical warfare agents. The results obtained with the MOFs will be compared with those obtained with a reference active carbon. Indeed, active carbons are currently used in gas masks to recover these species. However, their performance under different operating conditions (temperature variations, presence of moisture or contaminants such as hydrocarbons) remain relatively unknown. This can be a major issue in the current national and international context, which is experiencing an unprecedented rise in terrorism resulting in various kinds of attacks and in particular the recent use of chemical weapons in Syria. In addition, the operational areas of the military are constantly changing. Historically, it was rather a threat on the European continent. Today, a majority of operations are focused on the African continent or the Middle East, places on the globe where temperature and humidity changes between day and night are more important.
It is in this context that the SESAM project aims to explore the properties of a wide range of filter materials with respect to sarin and its simulants to better understand the capture behavior of these adsorbents and further to propose improvements of these filter materials to consider in the future an effective response to chemical threats whose spectrum is becoming wider. From an experimental point of view, to avoid the use of these highly toxic agents, simulants with physical and chemical properties similar to chemical weapons will be considered. It is well known that these molecules are characterized by low saturation vapor pressures and harmful effects at very low concentration, requiring the use of high resolution measuring instruments. Another challenge posed by this ambitious project will be to implement simulation tools that make it possible to accurately assess the performance of a wide range of filter materials with respect to these relatively complex molecules. The advantage of a numerical approach is that one can predict the behavior of both the simulants and live chemical agents.
The objective of this fundamental project is therefore to explore the performance of existing filter materials using both experimental and numerical high-throughput screening tools under various conditions in order to (i) ensure that the active carbons currently used maintain the same level of performance as a function of temperature, ambient humidity and in the presence of contaminants, (ii) to define which are the most appropriate simulants to mimic, as accurately as possible, the behavior of sarin and at therefore to provide simulant-sarin transfer functions; and (iii) to establish structure-property relationships in order to identify the ideal characteristics of the filter materials to capture a targeted molecule such as sarin.
SESAM brings together two groups with complementary skills recognized internationally in the field of adsorption (CNRS-MADIREL Marseille) and molecular simulation (CNRS-ICGM Montpellier), with the MADIREL group coordinating. These teams have been working together for many years in a ‘virtual’ laboratory and have the necessary know-how to contribute to major breakthroughs that address the thematic areas 6/7 and the NRBC component of the ANR / ASTRID project call.
The expected benefit for the defense sector of this project is that it can act as a springboard to establish new collaborations with end-users involved in the development of filter materials which can be applied to both civil and military security.