Solubility Determination and Modeling of <i>p</i>-Nitrobenzamide Dissolved in Twelve Neat Solvents from 283.15 to 328.15 K

Abstract

Through the shake-flask method, the solubility of p-nitrobenzamide in 12 pure solvents including n-propanol, ethanol, isopropanol, n-butanol, water, isobutanol, ethyl acetate, acetonitrile, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N-methyl-2-pyrrolidinone (NMP), and ethylene glycol (EG) was acquired over a temperature range from 283.15 to 328.15 K at ambient pressure p = 101.2 kPa. The mole fractions of p-nitrobenzamide in the equilibrium liquid phase increased as the temperature increased and had the following order in various solvents: DMSO > DMF > NMP > EG > ethyl acetate > ethanol > isopropanol > n-propanol > isobutanol > acetonitrile > n-butanol > water. They were fitted through the Wilson model, modified Apelblat equation, λh equation, and NRTL model. The maximum root-mean-square deviation value and relative average deviation value gained through the four models were, respectively, 56.69 × 10–4 and 6.55 × 10–2. The relative average deviation values achieved were smaller through the modified Apelblat equation than through the other equations for a given solvent. The mixing properties, infinitesimal concentration activity coefficient, and reduced excess enthalpy were derived. Additionally, using the relationship analysis of the Kamlet and Taft linear solvation energy of the solvent effect, the degree and type of interactions of solute–solvent and solvent–solvent were recognized.