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To improve the condensed-phase reaction rate of ε-CL-20, polydopamine (PDA)−nickel complex-coated multiwalled carbon nanotubes (CNTs) have been prepared and used as combustion catalysts. The PDA−Ni complex has been prepared and in situ coprecipitated with ε-CL-20 by an antisolvent crystallization process in its dimethyl sulfoxide (DMSO) solution. It has been shown that crystalline CL-20 composites included with PDA−Ni complexes are polygon-shaped with a smooth surface and an average diameter of 10−15 μm, whereas it is 140 μm for raw ε-CL-20 crystals. The catalytic reactivity of the complex on thermolysis of CL-20 has been investigated using the differential scanning calorimetry (DSC) and thermogravimetry (TG)coupled Fourier transform infrared (FT-IR) spectroscopy technique. It has been found that CNT@PDA−Ni complexes have catalytic effects on the decomposition of ε-CL-20 by decreasing/shifting of the exothermic peak from T p = 240.1 to 238.7 °C. The FT-IR spectra of CL-20 decomposition products under the effect of the catalyst predominantly show peaks at 1274, 1644 and 1596, 1912, 2265, and 1956−1800 cm −1 , indicating the presence of fragments with N 2 O, NO 2 , NO, HNCO, and NO/CO, respectively. The change in the ε-CL-20 decomposition mechanism should be attributed to the catalytic action of CNT, decreasing the formation of NO 2 . Also, under the effect of the carbon-based catalyst, the HNCO formation was detected at another temperature in comparison with raw CL-20, with peak absorption at 224.1 vs 232.3 °C and the evolution was completed at 250.8 vs 246.2 °C, respectively.

Combustion of hydroxylammonium nitrate (95 wt.% HAN) -water solution in presence of high specific surface area activated carbons is investigated in a constant-pressure bomb within the pressure range of 1-6 MPa. The linear burning rate increased for the system of HAN admixed with activated carbons compared to those of the HAN alone. Moreover, the thermal decomposition of HAN (95 wt.%) -water solution spiked with activated carbons was assessed by DTA -TG method. In the presence of activated carbons, the ability to trigger the decomposition at a lower temperature (86 °C vs 185 °C) was observed. The volatile products formed in the course of thermal decomposition of HAN, spiked with activated carbons were characterized by electron ionization mass spectrometry analysis. Primary products of HAN decomposition: m/z = 33 (NH 2 OH) and m/z = 63 (HNO 3 ), which are further responsible for the formation of secondary products such as N 2 O, NO, HNO 2 , NO 2 , O 2 etc. Significant reduction of NOx emissions during thermal decomposition of HAN (95 wt.%) -water solution was observed (ca. 30%) in presence of activated carbons.