Equilibrium Solubility of Domiphen Bromide in 12 Mono Solvents: Determination and Correlation

In this paper, the solubility of domiphen bromide in the range of 283.15–323.15 K was surveyed by the gravimetric method in 12 mono solvents of ethanol, n-propanol, n-butanol, 1-pentanol, iso-propanol, iso-butanol, tert-butanol, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), N-methyl-2-pyrrolidone (NMP), acetonitrile, and dimethyl sulfoxide (DMSO) at atmospheric pressure (0.1 MPa). The study results showed that the mole fraction solubility of domiphen bromide increased positively with increasing temperature. Among the selected 12 neat solvents, the solubility of domiphen bromide at 298.15 K followed the order 1-pentanol (0.1642) > n-butanol (0.1567) ≈ n-propanol (0.1572) ≈ ethanol (0.1569) > iso-butanol (0.1454) > iso-propanol (0.104515) > tert-butanol (0.08657) > NMP (0.05308) > DMF (0.04671) > DMSO (0.04505) > DMA (0.04156) > acetonitrile (0.009906). Thermodynamic models of the modified Apelblat model, the Yaws model, the Van't Hoff model, and the λh model were implemented to fit experimental solubility data of domiphen bromide, and the Yaws model yielded a relatively more accurate correlation result than the other three models by a comparison of the RAD and rmsd values. Experimental results would promote the separation and purification technology of drugs in the pharmaceutical industry.