Solubility determination and modelling for 4-nitrobenzaldehyde in N,N-dimethylformamide + (ethanol, n-propanol or n-butanol) mixed solvents

Abstract

The solubility of 4-nitrobenzaldehyde in mixed solvents of (N,N-dimethylformamide+ethanol), (N,N-dimethylformamide+n-propanol) and (N,N-dimethylformamide+n-butanol) were determined experimentally by using the isothermal dissolution method within the temperatures ranging from (273.15 to 313.15)K under atmosphere pressure (101.2kPa). The solubility of 4-nitrobenzaldehyde increased with increasing temperature and mass fraction of N,N-dimethylformamide for the binary systems of (N,N-dimethylformamide+ethanol), (N,N-dimethylformamide+n-propanol) and (N,N-dimethylformamide+n-butanol). At the same temperature and mass fraction of N,N-dimethylformamide, the mole fraction solubility of 4-nitrobenzaldehyde in ethanol was greater than those in the other two systems. The obtained solubility data were correlated by employing CNIBS/R-K model, Jouyban–Acree model, van't Hoff–Jouyban–Acree model, modified Apelblat–Jouyban–Acree and Sun model. The largest values of relative average deviation (RAD) and root-mean-square deviation (RMSD) between the experimental and calculated solubility were 0.92×10−2 and 6.22×10−4, respectively, which were obtained with Jouyban–Acree model for the system of N,N-dimethylformamide+n-propanol. On the whole, the CNIBS/R-K model was proven to provide better representation of the experimental solubility data. Based on the measured solubility, the dissolution enthalpies of the dissolution process were computed. Dissolution process of 4-nitrobenzaldehyde in these mixed solvents was endothermic. The experimental solubility and solubility models could be helpful in purifying 4-nitrobenzaldehyde from its isomeric mixtures.