Question

Streptomycin is extracted from the fermentation broth using an organic solvent in a counter-current staged extraction unit. The distribution coefficient of streptomycin at pH = 4 is KD = Yi/Xi = 40, and the flow rate of the aqueous (H) phase is H= 150 L/min. If only five extraction units are available to reduce the streptomycin concentration from 10 g/L in the aqueous phase to 0.2 g/L, determine the required flow rate of the organic phase (L) in the extraction unit.

Answer 1

Answer:

6.75l l/min

Explanation:

Streptomycin is extracted  from the fermentation broth using an organic solvent in a counter current staged extraction unit.

for 5 stage counter current staged extraction unit for streptomycin

X5 = 0.2g/l

X0 = 10.0g/l

X5/X0 = 0.02

given

Xn/X0, E, and

n = 5

A estimate of E  can be evaluated directly;

E = 1.8

= LKd/H

by substituting the given values; Kd = 40, H= 150l/min

then we have,

L;L = 1.8(150)/40

= 6.75l l/min