E. Bayraktar, Response surface optimization of the separation of DL-tryptophan using an emulsion liquid membrane, PROCESS BIO, 37(2), 2001, pp. 169-175
Response surface methodology was applied to optimize the separation Of DL-t
ryptophan from aqueous solution. DL-tryptophan was extracted into an emulsi
on liquid membrane containing Aliquat-336 in oleyl alcohol. The carrier con
centration (10-30%, by volume). pH (10-14) and initial amino acid concentra
tions (1-7 mM) were the critical components of the separation optimized. Ex
periments were performed at 150 rpm stirring rate, for 30 min extraction ti
me with equal volumes of organic and aqueous phases. The response surface e
quation to predict the extraction yield in the above range of critical comp
onents is
Y = 100.72 + 31.83x(1) + 0.15x(2) + 3.38x(3) - 21.41x(2)(1) - 5.39x(2)(2) -
7.11x(3)(2) + 1.19x(1)x(2) - 3.26x(1)x(3) - 2.30x(2)x(3)
where Y is the response. (extraction yield), Maximum Y (100%) was obtained
by employing the following predicted optimum extraction conditions: a pH of
12.46, a carrier concentration of 22.22%, and an initial amino acid concen
tration of 4.97 mM. (C) 2001 Elsevier Science Ltd. All rights reserved.