A comparison of two catalysts, magnesium chloride (MgCl2) and calcium chloride (CaCl2), have been studied to determine their effectiveness in aiding hydrogen release form Ammonia Borane (NH3BH3, AB), a probable chemical hydrogen storage candidate. AB contains a high weight percentage of hydrogen (19.6%) that could be exploited for usage in alternative fuels, making it a popular hydrogen carrier. Due to having a slow hydrogen release and production of unwanted byproducts, environmental applications have been restricted. Various studies have shown improved hydrogen release performance of AB with an addition of a polymer. Catalytic studies, moreover, have shown the addition of catalysts aid in lowering the activation energy, improving kinetics, and lowering the temperature of the first hydrogen release. Experimental procedures explored thermal and vibrational analysis of bulk AB composites with a polymer (i.e. polyvinylypyrrolidone and polyethylene oxide) and individual additions of MgCl2 and CaCl2 as catalysts. The bulk polymer-catalyst composites were prepared by mixing AB with polymer in different ratios and then vacuum drying. Dehydrogenation kinetics of the bulk composites were studied using a differential scanning calorimeter (DSC) and the data was compared with AB, bulk AB/polymer composites and analyzed. The results with catalyst exhibited a lower Ea than pristine AB and composites. Evidence of the interactions between the catalyst and polymer with pure AB were given by Fourier-transform infrared spectroscopy (FTIR) analysis. The data showed an improvement of the AB bulk composites in the regions where unwanted byproducts are of concern. Studies will also include thermogravimetric analysis (TGA) to determine the weight loss in composites with catalyst compared to pure AB and bulk composites along with observing the electronic structure and functional groups using NMR spectroscopy.

Catalyst effect on dehydrogenation of bulk ammonia borane-polymer composites

2019 Spring National Meeting

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