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The deactivation of a Pt/Ba/Al2O3 NOx-trap model catalyst submitted to SO2 treatment and/or thermal ageing at 800 °C was studied by H2 temperature programmed reduction (TPR), X-ray diffraction (XRD) and NOx storage capacity measurements. The X-ray diffractogram of the fresh sample exhibits peaks characteristic for barium carbonate. Thermal ageing leads to the decomposition of barium carbonate and to the formation of BaAl2O4. The TPR profile of the sulphated sample shows the presence of (i) surface aluminium sulphates, (ii) surface barium sulphates, (iii) bulk barium sulphates. The exposure to SO2 after ageing leads to a small decrease of the surface barium-based sulphates, expected mainly as aluminate barium sulphates. This evolution can be attributed to a sintering of the storage material. TPR experiments also show that thermal treatment at 800 °C after the exposure to SO2 involves the decomposition of aluminium surface sulphates to give mainly bulk barium sulphates, also pointed out by XRD. Thus, the thermal treatment at 800 °C leads to a stabilization of the sulphates. These results are in accordance with the NOx storage capacity measurements. On non-sulphated catalysts, the treatment at 800 °C induces to a decrease of the NOx storage capacity, showing that barium aluminate presents a lower NOx storage capacity than barium carbonate. Sulphation strongly decreases the NOx storage capacity of catalysts, whatever the initial thermal treatment, showing that barium sulphates inhibit the NO2 adsorption. Moreover, the platinum activity for the NO to NO2 oxidation is lowered by thermal treatments. [ABSTRACT FROM AUTHOR]

Highlights Prepregs are highly expensive, and most customers rely heavily on suppliers. The product may not always be optimized for specific applications, but it is sometimes the only commercially available option that works. To address these issues, there is a need to produce prepregs in‐house. In this article, we will describe the methodology for creating thermoset/thermoplastic hybrid prepregs using hot melt with B‐stage cured epoxy resin film. We investigated the choice of materials and the proportion of thermoplastics through DSC and rheology measurements. Additionally, we analyzed the time and temperature of B‐staging to achieve high‐quality composite parts. Multiple ways for preparing prepregs exists, each involving few different steps. We will explore some of these methods using a hydraulic press before scaling up to a prepreg filmer machine. Our focus will be on evaluating the quality of the final composites under various conditions and comparing them to composites produced with commercially available prepregs. In‐house thermoset/thermoplastic hybrid prepreg fabrication optimization procedure. Material characterization prior to fabrication to ensure B‐staging repeatability. Investigation of several methods of prepreg fabrication. Optimized procedure to achieve high‐quality surface finish for composite parts. [ABSTRACT FROM AUTHOR]