Effect of method of crystallization on the IV–III and IV–II polymorphic transitions of ammonium nitrate

Use of potassium ferrocyanide as habit modifier in the size reduction and phase modification of ammonium nitrate crystals in slurries

“…The samples obtained after same time interval but with Further analysis of the powder XRD patterns revealed that the non-matching diffraction lines (with JCPDS-ICDD data of AN) seen in the powder XRD patterns were matching with the diffraction lines of hydroxylammonium nitrate (HAN). Even the recrystallized samples [27] were showing the diffraction lines which coincided with that of JCPDS-ICDD data of monoclinic HAN; however, the HAN signature was more prominent in the samples obtained in the present study. In the powder XRD diffractograms, most of the higher intensity peaks were of AN and few of the lower intensity peaks were corresponding to HAN reflections.…”

“…However, our earlier studies revealed that recrystallized AN always shows a shift in IV ↔ III transition temperature at ∼50 • C, which falls back to 32 • C after one thermal cycling and the presence of trace amount of HAN contributes to this shift in transition [27]. Also, during the thermal cycling, some of the samples showed absence of the III ↔ II transition, which generally occurs at 84 • C. This anomaly is reported in the literature and said to have been influenced by the particle size [28].…”

Polymorphism in hexanitrohexaazaisowurtzitane crystallized from solution

“…The distinction may contribute to the anti-solvent properties (such as dipole moment, dielectric constant, polarity etc.) and solvent/anti-solvent interaction [33][34][35]. Thome [36] calculated the dipole moment of HNIW molecular during forms a (1.02 D), b (1.19 D), g (0.89 D), and e (0.75 D).The molecular of form b has a higher dipole moment than form e. Along with the addition of antisolvent, the molecules of HNIW are surrounded by the solution, which are polarized by the force filed of the polar anti-solvent and formed dipole-induced interaction.…”

Phase Stability of Ammonium Nitrate with Organic Potassium Salts

“…These have shown that the phase behavior of AN strongly depends on the experimental conditions, such as humidity [26], crystallization method [7], thermal history of sample [7], sample size [27], pressure [28,29], purity of sample [30], sample weight [31].…”