Dissolution properties of ammonium dipicrylamide in dimethyl sulfoxide and N-methyl pyrrolidone

The enthalpies of dissolution for ammonium dipicrylamide (ADPA) in dimethyl sulfoxide (DMSO) and N-methyl pyrrolidone (NMP) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure. Empirical formulae for the calculation of the enthalpies of dissolution (Delta H-diss) were obtained from the experimental data of the dissolution processes of ADPA in DMSO and NMP. The linear relationships between the rate (k) and the molality (b) were found. The corresponding kinetic equations describing the two dissolution processes were d alpha/dt = 10(-> 2.38)(1 - alpha)(0.86) for the dissolution of ADPA in DMSO, and d alpha/dt = 10(-2.49)(1 - alpha)(0.83) for the dissolution of ADPA in NMP, respectively. (C) 2012 Elsevier B.V. All rights reserved.