HAN (硝酸羥胺：NH3OHNO3)作為一種離子液體，其解離反應可以透過電解方式啟動，但其確實之機制仍不清楚。甚至有部分HAN基推進劑電解點火研究認為HAN的解離是由於電解水所伴隨之焦耳效應，導致溫度上升而誘發的，本質上仍為熱解離。因此本研究將對80 wt.% HAN水溶液於高壓下進行電解，探討電解時間內電解解離現象，釐清其解離機制究竟是透過電化學路徑還是焦耳效應所引發。另外HAN為高壓力依賴性之離子液體，容易受到壓力影響而影響燃燒特性，對於未來如要發展電解引燃推進器，勢必需對其高壓下HAN水溶液電解解離進行研究。
根據實驗結果表明電解解離確實為電化學反應，還伴隨著電解解離產物硝酸引發自催化反應；從電解80 wt.% HAN水溶液餘液分析中表明電解產物為硝酸，這進一步支持了前述之論點，硝酸將使HAN進行自催化解離，解離反應所產生之熱能將推動其自持反應。在高壓電解解離的過程中，電荷傳輸機制為Grotthuss機制。在本體溶液中佈滿密集的氫鍵網絡，質子從水分子一端藉由氫鍵網絡快速位移到遙遠一方，這種電荷傳輸機制是壓力依賴性。時序氣相產物分析中，表明解離氣體擁有H2O、HNO3以及氮氧化物NO、NO2、N2O；尾氣分析中，電解與熱解之氮氧化物比例以及不同壓力下都有所差異，再次表明電解解離確實為電化學反應。電解電壓則是決定反應是否發生之因子，電場強度則是會加速反應速率。濃度影響離子密度和液體黏度，這影響著電解反應速率。電解SHP163會有兩階段反應，並不適合作為電解引燃之推進劑。上述結果釐清電解HAN水溶液主要為電化學反應而不是熱解反應，以及壓力、電壓、成分對電解解離之影響，這些結果對於未來應用HAN基推進劑起了重要作用。

The electrolytic decomposition mechanism and the effect of pressure on the electrolytic decomposition of HAN aqueous solution have been discussed in this research. According to the experimental results, the electrolytic decomposition is indeed an electrochemical reaction, and the electrolytic decomposition product nitric acid also induces the autocatalytic reaction. A high nitric acid concentration at the anode during the electrolysis process accelerates the autocatalytic reaction, and the high concentration of hydroxylamine at the cathode inhibits the autocatalytic reaction. In high-pressure electrolytic decomposition, the grotthuss mechanisms is the main items affecting the decomposition of HAN. The time-resolved gas-phase product analysis shows that the decomposition gas contains H2O, HNO3, and nitrogen oxides NO, NO2, N2O, and the main products of electrolytic decomposition occur almost simultaneously. Gas analysis show the ratio of nitrogen oxides in electrolysis and thermal decompositions and under different pressures are different, again indicating that electrolysis is indeed an electrochemical reaction. The electrolysis voltage is the factor that determines whether the reaction will occur, and the electric field strength will accelerate the reaction rate. The concentration affects the ionic density and liquid viscosity, which affects the rate of the electrolytic reaction. Electrolysis of SHP163 will have a two-stage reaction and is not suitable as a propellant for electrolytic ignition. Overall, these results clarify electrolytic decomposition rather than thermal decomposition, which is vital for future applications of electrolysis to ignite HAN-based propellants.

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