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Bio-Rad AG® MP-1M Anion Exchange Resins User Manual

Page 8

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11

Section 4
Resin Conversion

Table 5 outlines common techniques for converting

ion exchange resins from one ionic form to another.

Resin conversion is most efficiently carried out in the
column mode. However, when choosing a column,
remember that the resin may shrink, or it may swell as
much as 100%, depending on the conversion.

10

Table 5. Techniques for Resin Conversion

Volumes of

Linear

Test for

Rinse:Vol.

Test for

Conversion

Sol’n/Vol.

Flow Rate

(4)

Type of

Completeness

Dl Water/

Completion

Resin

From

To

(1)

Reagent Used

of Resin

cm/min of Bed

Exchange

(3)

of Conversion

Vol. Resin

of Rinsing

AG 1 and

Cl

OH

1 N NaOH

(2)

20

IX

Cl

–(5)

4

pH<9

AG MP-1

OH

formate

1 N formic acid

2

2

N

pH<2

4

pH>4.8

Resins

Cl

formate

Use Cl

OH

and

20

IX-N

pH>4.8

then OH

formate

2

pH>4.8

Cl

acetate

same as formate except

IX-N

pH<2

4

pH>4.8

use 1 N HAc

AG 2 Resin

Cl

OH

1 N NaOH

(2)

2

2

IX

Cl

–(5)

4

pH>9

Cl

NO

3

0.5 N NaNO

3

5

IX

Cl

(

5)

4

1. Typical conversions are listed. The same reagents can be used to con-

vert from other ionic forms. Two steps regeneration, ion exchange fol-
lowed by neutralization, is included because of ease of conversion and
saving on expensive reagents.

2. Use U.S.P. or C.P. grade (low chloride).

3. N = Neutralization; IX = Ion exchange; IXN = two step process: Ion

exchange to acid or base form followed by neutralization with appro-
priate base or acid of salt, example (Step 1) Resin-Cl

+ NaOH

Resin-OH (IX); (Step 2) Resin-OH + H-formate

resin-formate +

H

2

O (neutralization).

4. For 50-100 or finer mesh resin. For 20-50 mesh about

1

5

the flow rate

is recommended

5. Test for Cl

in effluent: Acidify sample with a few drops of conc.

HNO

3

. Add 1% Ag NO

3

solution. White ppt indicates Cl

, yellow Br

or too basic.

LIT212C 6/17/98 12:25 PM Page 10