Page:NIOSH Manual of Analytical Methods - 6002.pdf/2

 PHOSPHINE: METHOD 6002, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10 11. 12. 13.

14.

15. 16. 17.

18. 19.

20.

EQUIPMENT:

Potassium dihydrogen phosphate, anhydrous, KH2PO4, ACS reagent grade Sulfuric acid, concentrated, ACS reagent grade Ammonium molybdate,(NH4)6Mo7O24·4H2O Ferrous ammonium sulfate, Fe(NH4)2(SO4)2 Potassium permanganate, KMnO4 Stannous chloride, SnCl2 Glycerol Toluene Isobutanol .Methanol Water, deionized or distilled. Mercuric cyanide, Hg(CN)2* Standard phosphate solution. Dissolve 200 mg KH2PO4 in 1 L of distilled water. (1.00 mL = 49.94 µg PH3) Molybdate solution. Dissolve 49.4 g (NH4)6Mo7O24·4H2O and 112 mL concentrated H2SO4 in distilled water to a total volume of 1 L. Alcoholic sulfuric acid solution. Add 50 mL of concentrated H2SO4 to 950 mL methanol. Toluene-isobutanol solvent. Mix equal volumes of toluene and isobutanol. Ferrous solution. Dissolve 7.9 g Fe(NH4)2(SO4)2 and 1 mL concentrated H2SO4 in water to a total volume of 100 mL. Stannous chloride solution. Dissolve 0.4 g SnCl2 in 50 mL glycerol (heat to dissolve). Acidic permanganate solution. Dissolve 0.316 g KMnO4 and 6 mL concentrated H2SO4 in 1 L water. Mercuric cyanide solution.* Dissolve 2 g Hg(CN)2 in 100 mL water.

1.

2.

3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.

Sampler: Glass tube 12-cm long, 6-mm O.D., 4-mm I.D., flame-sealed ends with plastic caps, with two sections of mercuric cyanide-treated silica gel (45/60 mesh), (front = 300 mg, back = 150 mg), separated and retained by silylated glass wool plugs. (See Appendix) Personal sampling pump, 0.01 to 0.2 mL/min, with flexible polyethylene or PTFE tubing. Spectrometer capable of measuring absorbance or transmittance at 625 nm. Two matched 5-cm absorbance cells, silica, with tight fitting caps. Separatory funnel, 125-mL. Beakers, 50-mL. Pipets, 0.2-, 10-, and 25-mL, and other convenient sizes to make standard dilutions. Volumetric flasks, 10-, 25-, 100-, and 1000mL. Water bath (maintained at 65-70C). Graduated cylinders, glass, 10-mL. Syringes, 0.5- and 1.0-mL. Balance. Thermometer. Stopwatch. Barometer.


 * See Special Precautions

SPECIAL PRECAUTIONS: Caution should be exercised when preparing the sampling media because mercuric cyanide is toxic. Work only in a hood.

SAMPLING: 1. 2.

3. 4.

Calibrate each personal sampling pump with a representative sampler in line. Immediately before sampling, break the ends of the silica gel tubes to provide an opening of at least one half the internal diameter of the tube. Attach the silica gel tube to the sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 1 to 16 L. Seal tubes with plastic (not rubber) caps.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition