Extraction Equilibria of Acrylic Acid from Aqueous Solutions by Amberlite LA-2 in Various Diluents.

Amberlite LA-2 (a secondary amine mixture) has been studied for its ability to extract acrylic acid at different amine concentrations. The extraction of acrylic acid by Amberlite LA-2 dissolved in seven single solvents (cyclohexane, 2-octanone, toluene, methyl isobutyl ketone (MIBK), iso-octane, hexane, and 1-octanol) has been investigated with respect to different amine concentrations at 298.15 K. In the extraction, two acid−amine complexes, (HO):(R2N) and (HO):(R2N)2, have been assumed to exist in the organic phase in the case of proton-donating diluents, while the complexes (HO):(R2N) and (HO)2:(R2N)3have been suggested in the case of nonproton-donating diluents. Important data for the design and analysis of different separation processes have been obtained as a result of batch experiments. These important data are distribution coefficients (D), loading factors (Z), extraction efficiency (E), and overall extraction constants (K11, K12, K23). The maximum removal of acrylic acid is 98.22 % with MIBK at 0.93 mol·L−1initial concentration of Amberlite LA-2. [ABSTRACT FROM AUTHOR]