LaMotte TL-2 User Manual

De ter mi na tion of Tetrakishydroxymethyl

Phosphonium Sul fate (THPS)

in Tolcide® PS Biocides

CODE 4-8776

QUANTITY CONTENTS CODE

120 mL *DSP Reagent, 10% Solution *4133-J
120 mL *Borate Buffer Solution *4135-J
120 mL *PSSA Reagent, 5% Solution *4134-J
30 mL Starch Indicator Solution 4170WT-G
60 mL *Iodine Solution, 0.025N *6377-H
15 mL *Zinc Acetate, 2N *3843-E
1 Test Tube, plastic, 5-10-25 mL, w/cap 0715
3 Pipets, 1 mL, plastic 0354
1 Direct Reading Titrator, 0 - 100 Range 0381
1 Dispenser Cap 0601

*WARNING: Reagents marked with a * are considered hazardous substances.
To view or print a Material Safety Data Sheet (MSDS) for these reagents see
MSDS CD or our website. To obtain a printed copy, contact us by e-mail, phone
or fax.

To order individual reagents or test kit components, use the specified code
number.

INTERFERENCES: Hydrogen sulfide can interfere with the
determination of THPS. Pretreatment with zinc acetate will remove the
interference. Add 5 drops of *Zinc Acetate, 2N (3843) for every 100 ppm
hydrogen sulfide present in a 50 mL sample. Filter off the white precipitate
that forms and proceed with Steps 1-11 using the filtrate.

PRO CE DURE

1. Fill the test tube (0715) to the 25 mL line with the sample to be
tested.

2. For fresh water samples, use a 1 mL pipet (0354) to add 2.0 mL *DSP
Reagent, 10% Solution (4133). For saltwater samples, use another
1 mL pipet (0354) to add 2.0 mL *Borate Buffer Solution (4135).

3. Use another 1 mL pipet (0354) to add 2.0 mL of *PSSA Reagent, 5%
Solution (4134). Swirl to mix.

4. Add 6 drops of Starch Indicator Solution (4170WT). Swirl to mix.

5. Replace the regular cap on the bottle of *Iodine Solution, 0.025N

(6377) with the special dispenser cap (0601).
NOTE: Replace the regular cap on the Iodine Solution 0.025N

bottle for storage.

6. Fill the Direct Reading Titrator (0381) with the *Iodine Solution,

0.025N (6377).

7. Slowly add *Iodine Solution, 0.025N (6377) to the test tube by
depressing the plunger. Swirl the test tube after each drop to mix
reagents.

8. Continue adding *Iodine Solution, 0.025N (6377) until 1 drop
results in a permanent blue/black color.

9. Read the concentration (in ppm) of THPS directly from the scale on
the Titrator.

NOTE: Take the titrator reading where the plunger meets the
titrator scale. Each small division is equal to 2 ppm.

10. Repeat Steps 1-9 on a blank (system water without biocide) to
determine background levels.

11. Subtract the blank reading from the reacted sample reading to
determine the concentration of THPS in the sample.

NOTE: This test measures ppm active THPS. To obtain ppm of
formulation, divide ppm THPS by the activity (in percent) of the
formulation, and multiply by 100.

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PO Box 329 • Chestertown • Mary land • 21620 • USA

800-344-3100 • 410-778-3100 (Out side U.S.A.) • Fax: [phone]

Visit us on the web at www.lamotte.com

®

68776 04.04