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International audience; Boththe Sample Analysis at Mars (SAM) and Mars Organic Molecule Analyzer (MOMA)instrumentsare able to identify organic material at the Martian surface and subsurface. Both experiments are equipped with pyrolysis-Gas Chromatography-Mass Spectrometry (Pyr-GC-MS)and derivatization reagents (MTBSTFA)that will allowthe analyzerefractory com-pounds,making them more volatile and protecting the labile chemical groups. In order to improve the Pyr-GC-MS analysis, TMAH (tetramethylammonium hydrox-ide) will be used on MOMA and SAM to extract refrac-tory compounds (macromolecules, kerogen, etc.) and protect polar compounds released from the pyrolysis ex-periment.We performed pyrolysis and TMAH-thermochemolysis of a Martian regolith simulant (JSC-Mars-1) to optimizeanalytical parameters, especially the thermochemolysis temperature, to ensure the success of the near future in situthermochemolysis analyses on Mars.

The development of the large European biomethane potential is facing the challenge of the biogas upgrading technologies adaptation to the agricultural context (small and medium size anaerobic digestion units, rural environment). Membrane contactors are an opportunity to adapt the robust Water Scrubbing (WS) process and to decrease the high specific investment costs reported for available technologies. Microporous polypropylene (PP) hollow fiber membrane contactors were combined in an absorption/desorption closed-loop using water as the absorbent. A Design of Experiments methodology highlighted the gas and liquid flowrates, the inlet biogas composition and the absorption gas pressure to be the most significant parameters impacting biomethane quality with a low level of interactions. From the subsequent optimization, gas-grid quality biomethane (......4......=97.6%) was produced with a moderate recovery rate (......4=83.7%). The limited mass transfer efficiency may be compensated by a larger membrane area. Alternatively, the addition of a methane recycling loop, similarly to the conventional WS process, significantly improved the methane recovery rate (......4......=95.9% / ......4=93.5%). These experimental results were confirmed by on-site upgrading of raw farm biogas., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 1116-1125

International audience; After the SAM experiment onboard the Curiosity rover, the Mars Organic Molecule Analyzer (MOMA) experiment onboard the future ExoMars mission will be the continuation of the search for the organic composition of the Mars surface. MOMA will have the advantage of extracting the sample from as deep as 2 meters below the martian surface to minimize effects of radiation and oxidation on organic materials. To analyse the wide range of organic compounds (volatile and non volatils compounds) penten-tially present in the martian soil MOMA includes two operational modes: UV laser desorption / ionization ion trap mass spectrometry (LDI-ITMS) and pyrolysis gas chromatography ion trap mass spectrometry (pyr-GC-ITMS). In order to analyse refractory organic compounds and chirality samples which undergo GC-ITMS analysis may be submitted to a derivatization process, consisting in the reaction of the sample components with specific reactants (MTBSTFA [1], DMF-DMA [2] or TMAH [3]). To prove the feasibility of the derivatization within the MOMA conditions we have adapated our laboratory procedure to the space conditions (temperature, time, pressure and size) in order to decrease our detection limits and increase the range of the organic compounds that MOMA will be able to detect. Here, we only discuss the optimization of the thermochemiolysis technique.

International audience; Sample Analysis at Mars (SAM) is one of the instruments of the MSL mission. Three analytical devices are onboard SAM: the Tunable Laser Spectrometer (TLS), the Gas Chromatography (GC) and the Mass Spectrometer (MS). To adapt the nature of a sample to the analytical devices used, a sample preparation and gas processing system implemented with (a) a pyrolysis system, (b) wet chemistry: MTBSTFA and TMAH (c) the hydrocarbon trap (silica beads, Tenax® TA and Carbosieve G) and the injection trap (Tenax® GR composed of Tenax® TA and 30% of graphite) are employed to concentrate vol-atiles released from the sample prior to GC-MS analysis [1]. This study investigates several propositions for chlo-rinated hydrocarbon formation detected in the SAM background by looking for: (a) all products coming from the interaction of Tenax® and perchlorates, (b) also between some soil sample and perchlorates and (c) sources of chlorinated hydrocarbon precursors. Here we report on the detection of chlorohydrocarbon compounds and their potential origin.

An electronic pulsed power supplier for High Intensity Discharge (HID) lamps is presented in this paper. The pulsed power supplier is obtained from the integration of a two current source AC/DC converter and a full-bridge inverter. The electronic supply provides to the lamp a different current form excitation (crenels and superposition of pulses). The lamp is represented in a model of simulation by its conductance model and coupled to its electronic power supply. Finally, some experimental results from a laboratory prototype are shown and compared with simulation. The general objective of this work consists in studying the effect of a current pulsed power supply on the electric and photometric behaviour of the discharge lamps, intended in particular for photochemistry.

International audience; In the frame of the future MOMA experiment of the European Exomars 2013 space mission aimed at finding traces of life, our work deals with the optimization of the derivatization parameters of chiral organic molecules such as amino acids using N,N- Dimethylformamide Dimethylacetal (DMF-DMA) as derivatizing agent. In order to optimize the chiral derivatization, within space operating conditions, several parameters such as temperature (90 to 170C) and reaction time (30 s to 60 min) have been studied using a Chirasil-Dex capillary column for the enantiomeric separation. This technique performed in one-step reaction is space compatible and allows to identify 18 out the 20 proteogenic amino acids and to separate enantiomerically 11 out of the 19 ones (glycine being non-chiral) with a single column using -cyclodextrin stationary phase. In a second step, the racemization rate, which varies according to the nature of the amino acid, has been studied under the optimal conditions of derivatization. Racemization is all the more important since temperature is the key factor of this phenomenon. The higher the temperature, the faster will the racemization be. Thus, for example when only D-form of threonine is injected, the D-enantiomeric excess drops from 100 to 28 when the temperature used for the derivatisation is increased from 70 to 150C, this drop being respectively 72 and 60 at 90 and 120C. The optimal heating time of the derivatization reaction has been also determined allowing high derivatization efficiency and low rate of racemization of the enantiomers and destruction of the amino acids. Quantitative studies were also carried out: linearity studies and the measurement of the limit of detection (LOD) show that the proposed method is suitable for a quantitative determination of enantiomers of several amino acids within a limit of detection (lower than the ppb level) compatible with that found in Martian meteorites.