1. ERT 313 BIOSEPARATION ENGINEERING TUTORIAL 3 - ADSORPTION
Prepared by:
Miss Hairul Nazirah Abdul Halim

2. QUESTION 1 Example 25.2 (McCabe)
The adsorption of n-butanol from air was studied in a small fixed bed (10.16 cm diameter) with 300 and 600 g carbon, corresponding to bed lengths of 8 and 16 cm.
a) Plot the breakthrough curve
b) From the following data for effluent concentration, estimate the saturation capacity of the carbon and the fraction of the bed used at c/co = 0.05

3. Data for n-butanol on Columbia JXC 4/6 carbon are as follows:

5. Solution
The total solute adsorbed is the area above the graph multiplied by FA . For the 8-cm bed, the area is
How to solve this integration???

7. Use numerical integration (5-point quadrature formula)
From the graph plotted, the following data is obtained: t
c/co
f (X) = 1-c/co 1 2
0.027
0.973 4
0.29
0.71 6
0.78
0.22 8
0.99
0.01

8. How to solve this integration???
The mass of carbon per unit cross-sectional area of bed is
= bed length x density of carbon
= 8 cm x 0.461g/cm3 = 3.69 g/cm2
Equilibrium or saturation value, Wsat
How to solve this integration???

9. Use numerical integration (Trapezoidal rule)
From the graph plotted, the following data is obtained: t
c/co
f (X) = 1-c/co 1
2.4
0.05
0.95

10. For L = 8cm, 50% of the bed capacity is unused.

11. Question 2
Adsorption of an organic solute on activated silica gel gave the following data after equilibration. Fit the data to an adsorption isotherm and calculate the constants.
C (mg/L)
0.139
0.089
0.066
0.047
0.037
W (mg/g)
0.03
0.026
0.0225
0.021
0.018