Reactive extraction of pimelic (heptanedioic) acid from dilute aqueous solutions using trioctylamine in decan-1-ol

The present study is on the reactive extraction of pimelic acid (heptanedioic acid) from dilute aqueous solutions by trioctylamine (TOA) in decan-1-ol. The equilibrium studies were performed at 298 K and the results were used to calculate the values of distribution coefficient (K-D), loading factor (Z) and degree of extraction (E%). The maximum K-D was obtained as 6234 when initial concentrations of pimelic acid and TOA were 0.038 and 0.2 mol(-1) kg(-1), respectively. The extraction efficiency was 98.27% under these conditions. Moreover, Z values between 0.184 and 2.934 were obtained in the ranges of parameters studied. The data presents the formation of 1:1 and 1:2 pimelic acid-TOA solvates in the organic phase. A solvatochromic model (LSER) was applied to the equilibrium data and the K-D values obtained using the model show a good fit to the experimental outcomes. (C) 2016 Elsevier B.V. All rights reserved.