Method for determining an effective peclet number for a membrane adsorber device

1. A method for determining an effective Peclet number for a membrane adsorber device comprising the steps of: (a) equilibrating the membrane adsorber device with an equilibration buffer at a known pH and conductivity; (b) challenging the membrane with a known concentration of a specific solute in said equilibration buffer; (c) monitoring the breakthrough of the solute downstream of the membrane as a function of a value selected from the group consisting of time, challenge volume and other suitable variable related to total quantity of material challenged to membrane adsorber device; (d) analyzing the solute breakthrough curve to determine pertinent flow characteristics of said membrane adsorber device by calculating the sharpness of the breakthrough curve of said membrane adsorber device; and (e) comparing the results calculated in step (d) to results from known integral devices to determine the effective Peclet number.

2. The method of claim 1 wherein step (c) is performed by a detector.

3. The method of claim 1 wherein step (d) is performed by monitoring the time of solute breakthrough.

4. The method of claim 1 wherein step (d) is performed by monitoring a variable related to the total quantity of material challenged to said membrane adsorber device at a point in time selected from the group consisting of the initial onset of solute breakthrough and a fraction of said solute breakthrough.

5. The method of claim 1 wherein step (d) is performed by monitoring a variable related to the total quantity of material challenged to said membrane adsorber device at a specific fraction of solute breakthrough.

6. The method of claim 5 wherein said fraction is from about 5% to about 50%.

7. The method of claim 5 wherein said fraction is from about 5% to about 20%.

8. The method of claim 5 wherein said fraction is from about 5% to about 10%.

9. The method of claim 1 wherein step (d) is performed by calculating a breakthrough curve sharpness and an initial onset of solute breakthrough.

10. A method for calculating an effective Peclet number for a membrane adsorber device comprising the steps of: (a) equilibrating the membrane adsorber device with an equilibration buffer at a known pH and conductivity; (b) challenging the membrane with a known concentration of a specific solute in said equilibration buffer; (c) monitoring the breakthrough of the solute downstream of the membrane as a function of a value selected from the group consisting of time, challenge volume and other suitable variable related to total quantity of material challenged to membrane adsorber device; (d) fitting the equation:

C A /C 0 =½*{1+ erf [[( Pe ) 1/2 *( V−V bar )]/[2 *[V*V bar ] 1/2 ]]}

where

C A is the effluent solute concentration

C 0 is the inlet solute concentration

V is the challenge volume

V bar is the challenge volume at 50% breakthrough (C A /C 0 =0.5)

Pe is the effective Peclet number

to said experimentally determined breakthrough curve to determine the effective Peclet number.

11. The method of claim 10 wherein step (d) is performed using a least-squares fit.

12. The method of claim 10 wherein step (d) is performed using a multipoint method.

13. The method of claim 12 further comprising the steps of: (e) using said equation to develop a generic plot of Pe versus (V 90 −V 10 )/V 50 ; (f) determine V 10 , V 50 and V 90 from said experimentally determined breakthrough curve, and (g) finding Pe from said generic plot using said experimentally determined values of V 10 , V 50 and V 90 wherein V 10 , V 50 , and V 90 are the breakthrough volumes corresponding to 10, 50, and 90% solute breakthrough, respectively.