Membranes - Principles of Chemical Separations with Environmental Applications - page 265

Table 9.7 Results of membrane performance, Example 9.6.

Organic-water mixtures: feed

Fugacity,

f org (kPa)

P i sat (kPa)

wt% organic x i (mole frac.) γ i

Ethanol 5 0.0202 6.19 10.39 1.30

Acetic acid 5 0.0155 2.79 2.77 0.12

Acetone 5 0.0161 11.64 38.04 7.13

Corresponding values for water

Fugacity,

f wat (kPa)

P i sat (kPa) wt% water x j (mole frac.) γ j

Ethanol 95 0.9798 1.006 4.23 4.17

Acetic acid 95 0.9845 1.004 4.23 4.18

Acetone 95 0.9839 1.004 4.23 4.18

Permeate P p = 0 . 5kPa

Water flux, N j Organic flux, N i y j (water) y i (org.)

(kg/m 2 · hr) (kg/m 2 · hr) wt% water (mole frac.) (mole frac.)

Ethanol 0.063 0.157 71.4 0.506 0.494

Acetic acid 0.066 0.0094 12.5 0.9589 0.0411

Acetone 0.035 0.289 89.2 0.281 0.719

Permeability calculated from Eqn (9.20)
Q

hr · kPa

Q

hr · kPa

kg · m
m 2

kg · m

m 2

· ·

(organic) (water)

1.24 × 10 − 12 1.34 × 10 − 13

Ethanol

7.88 × 10 − 13 1.49 × 10 − 13

Acetic acid

3.56 × 10 − 13 7.22 × 10 − 14

Acetone

Using Eqns (9.21)-(9.24)

β pervap β evap β mem

Ethanol 47 15.13 3.11

Acetic acid 2.71 1.76 1.54

Acetone 157 104.3 1.50