Membrane

 

Module

 

pH

 

s

Pm
(cm/sec)

Selenate

 

ESNA

Spiral-wound

 

10

 

0.85

7.110-6

ESNA

Spiral-wound

 

7

 

0.82

6.810-6

ESNA

Spiral-wound

 

4

 

0.84

6.910-6

GM

Flat-sheet

 

10

 

0.62

2.310-4

GM

Flat-sheet

 

7

 

0.43

2.210-4

GM

Flat-sheet

 

4

 

0.19

2.010-4

 

PW

Flat-sheet

 

10

 

0.51

1.710-3

Selenite

 

ESNA

Spiral-wound

 

10

 

0.80

7.010-6

ESNA

Spiral-wound

 

7

 

0.61

6.910-6

ESNA

Spiral-wound

 

4

 

0.31

6.910-6

GM

Flat-sheet

 

10

 

0.31

2.210-4

GM

Flat-sheet

 

7

 

0.13

2.210-4

PW

Flat-sheet

 

10

 

0.11

1.710-3

Table 2: Estimated transport coefficients.