Thermochemical Properties of Dissolution of Nitroguanidine in Dimethyl Sulfoxide and N,N-Dimethylformamide

Abstract

Abatract. The enthalpies of dissolution for nitroguanidine (NQ) in dimethyl sulfoxide (DMSO) andN,N-dimethylformamide (DMF) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K. Empirical formula for the calculation of the enthalpies of dissolution (ΔdissH) was obtained from the experimental data of the dissolution processes of NQ in DMSO and DMF. The corresponding kinetic equations describing the dissolution processes were dα/dt=10-1.49(1-α)0.94for the dissolution of NQ in DMSO and dα/dt=10-1.59(1-α)0.90for the dissolution of NQ in DMF.

Preparation of Ultrafine Nitroguanidine by One-Step Crystallization in an Impinging Stream-Rotating Packed Bed

“…Ruslan et al 1 obtained ultrafine NQ with a bulk density of 0.81 g/mL by controlling the cooling rate of supersaturated NQ aqueous solution containing methylcellulose (MCE) and poly(vinyl alcohol) (PVA), and the mechanical and combustion properties of NQ were significantly improved. In case of the organic solvent method, some organic substances (DMF, 8 DMSO, and NMP 9 ) were often used as solvents to dissolve NQ, and then, the solution along with anti-solvents was used to precipitate ultrafine NQ. Li et al 6 prepared ultrafine NQ using N-methylpyrrolidone (NMP) and acetone as the solvent and anti-solvent, respectively, and its bulk density could reach 0.94−0.97 g/cm 3 .…”