Partition coefficients and solubilities of glycine in the ternary solvent system 1-butanol + ethanol + water

For solvent extraction of biomolecules, usually optimized blends of one or more solvents and/or other compounds are required. Often the amount of experimental data and relevant thermodynamic models is very limited. In this report, we give partition coefficients and solubilities of glycine in the solvent system 1-butanol + ethanol + water at a temperature of 25°C. Additionally, at the same temperature, liquid - liquid equilibria are given for mixtures of 1-butanol + ethanol + water + glycine as well as densities of the coexisting phases. The experimental results have been correlated to a one-parameter excess Gibbs model, using both the phase behavior of the glycine-free solvent system and the solubilities of glycine in the single solvents. Considering the simplicity of the model, its predictions were found to be in good agreement with the experimental results.