Extraction of acetate from simulated waste solutions in chloromycetin production

Four extractants including Alamine 336 (tri-n-octyl/decyl amines), Aliquat 336 (tri-n-octylmethylammonium chloride), TOPO (tri-n-octylphosphine oxide), and TBP (tri-iz-butylphosphate) in xylene were used to evaluate the possibility of recovering acetate from simulated waste streams in chloromycetin production (typically, 15.4% acetic acid, 8.8% sodium acetate, and 4.7% w/w NaCl). Different stripping agents including water, NaOH, Na2CO3, HCl, and H2SO4 were tested. The optimal recovery conditions were determined according to the extractability, economy, and stripping efficiency. It was shown that the Aliquat 336/Na2CO3 was the best choice, although it had problems with phase separation due to emulsion formation. The second alternative was the TBP/Na2CO3; although it gave a worse performance, it was less expensive and had no problems with phase separation. (C) 1999 Elsevier Science B.V. All rights reserved.