Concentration and diafiltration with an Ultrafiltration System. A 2000 liter
volume of a 30 g/liter protein solution needs to be first concentrated in Step 1. In Step 2, the
initial salt concentration must be reduced one hundred fold using constant volume
diafiltration. In Step 3, the protein solution needs to be concentrated to 200 g/liter. The
relationship between the permeation rate and the bulk protein concentration has been
determined experimentally as follows: Q = 500* ln(270/Cb), where Q = permeation rate
(liters/hour) and Cb = bulk protein concentration (g/liter). Answer the following:
a. Determine the initial volume that needs to be reached after the first concentration
step to minimize the time for diafiltration. Increment the volume drop by 100 liters
each step.
b. Estimate the time Step 1 will take.
c. Estimate the time Step 2 will take. Assume 0% retention of the salt by the
membrane.
d. Estimate the time Step 3 will take.
