Liquid-liquid equilibria of gluconic acid between water and trin-n-octylamine in various diluents

摘要

Gluconic acid, C_6H_(12)O_7, is used for a large number of different industrial applications due to some exceptionally useful properties. However, data about gluconic acid and tri-n-octylamine/diluent system are not available in literature. The aim of this study is to investigate the extraction of gluconic acid from aqueous solutions by tri-n-octylamine dissolved in a variety of diluents a in wide range of amine concentrations (0.23-1.72 mol/L). Extraction equilibria of gluconic acid in the system solution of tri-n-octylamine in mixtures with 5 various solvents at temperature 298.15 K have been measured. Diluting solvents used in this study are hexane, cyclohexane, toluene, methyl isobutyl ketone (MIBK) and propanol. Using Bizek approach three acid: amine complexes, (Acid)·(Amine); (Acid)·(Amine)_2 and (Acid)_2·(Amine)_3 have been assumed to exist in organic phase. As a result of batch extraction experiments distribution coefficients, loading factors and overall extraction constants were calculated.