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DOE OSTI · 1860808

Solid state NMR Investigation of Structural Differences in Pelletized DEB Samples

Mason, Harris E.·Colla, Christopher A.·Matt, Sarah M.·Dinh, Long N.
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Abstract

Upon hydrogenation of DEB pellets, which are composed of 75% virgin DEB and 25% of nanometer scale Pd catalysts on activated carbon, the uptake rate is strong, and the hydrogenation process is fast. However, the last batch of DEB pellets from KCNSC uptakes 10 times slower than traditional DEB pellets after ~ 50% consumption. In addition, the last batch of DEB getter pellets also became partially molten/wet during the hydrogenation process. This molten/wet phase during hydrogenation has only been observed with DPB and never with DEB formulation. DRIFT (diffuse reflection infrared Fourier transform) and XRD (x-ray diffraction) confirm that the questionable batch of DEB pellets from KCNSC are truly 100% DEB and not a mixture of DEB and DPB. So, there must be something different in the composition (like concentration and distribution of Pd) or interaction between the DEB molecules with the surrounding environment (activated carbon spreading medium). The possibility of some chemical contamination in the processing of this batch of questionable DEB getter pellets also comes to mind. Due to the ability of NMR to detect intermolecular interaction and sensitivity to small chemical concentration, NMR investigation was requested for this questionable batch of DEB getter pellets from KCNSC.

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Mason, Harris E., Colla, Christopher A., Matt, Sarah M., Dinh, Long N.. 2022-02-08. Solid state NMR Investigation of Structural Differences in Pelletized DEB Samples. https://doi.org/10.2172/1860808

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