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The objectives of this study were to prepare a high-purity hydroxylammonium nitrate (HAN) solution and evaluate the performance of various types of metal oxide/honeycomb catalysts during the catalytic decomposition of the HAN solution. Hydroxylammonium nitrate was prepared via a neutralization reaction of hydroxylamine and nitric acid. FT-IR was used to analyze the chemical composition, chemical structure, and functional groups of the HAN. The aqueous HAN solution obtained from pH 7.06 showed the highest concentration of HAN of 60% and a density of 1.39 g/mL. The concentration of HAN solution that could be obtained when the solvent was evaporated to the maximum level could not exceed 80%. In this study, catalysts were prepared using a honeycomb structure made of cordierite (5SiO2-2MgO-2Al2O3) as a support, with Mn, Co, Cu, Pt, or Ir impregnated as active metals. The pore structure of the metal oxide/honeycomb catalysts did not significantly depend on the type of metal loaded. The Cu/honeycomb catalyst showed the strongest effect of lowering the decomposition onset temperature in the decomposition of the HAN solution likely due to the intrinsic activity of the Cu metal being superior to that of the other metals. It was confirmed that the effect of the catalyst on the decomposition mechanism of the aqueous HAN solution was negligible. Through a repetitive cycle of HAN decomposition, it was confirmed that the Cu/honeycomb catalyst could be recovered and reused as a catalyst for the decomposition of an aqueous HAN solution.

This study presents a detailed design, cost estimation and sensitivity analysis to determine the commercial viability of a Jatropha biodiesel plant with Nepal as a representative case. Here, we present a biodiesel production process utilizing dolomite PB-20, an inexpensive solid catalyst, that allows easy retrieval of catalysts for reuse and easier product separation compared to the conventional liquid catalyst based production process. The transesterification and the subsequent separation processes were simulated using Aspen Plus to determine the amount of raw materials, the sizes of the equipment's and the total utility required for producing 43 million liters biodiesel per year. The total capital cost and the production cost for the plant of this scale was calculated to be $23 million and $51 million respectively. Similarly, the final biodiesel selling price was calculated to be $1.23/l. The selling price of the biodiesel was found to be highly sensitive to the purchase cost of the Jatropha oil. A 25% reduction in the Jatropha oil purchase cost from the base case price of $0.97/l will lower the biodiesel selling price to $1.00/l making it competitive with petro-diesel (current selling price of $1.02/l). The economic viability of the dolomite catalyst based biodiesel production plant and thus, the adoption of biodiesel as a substitute for petro-diesel is strongly dependent on the purchase cost of the Jatropha oil. This study illustrates the potential of dolomite catalyst based biodiesel production process and provides an important reference value for a more detailed policy level study to develop appropriate biofuel policies and to make investment decisions.