Page:NIOSH Manual of Analytical Methods - 2012.pdf/2

 n-BUTYLAMINE: METHOD 2012, Issue 1, dated 15 August 1994 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. 2. 3. 4. 5. 6. 7.

n-Butylamine,* ACS reagent grade. Potassium hydroxide,* (KOH) 1 N, ACS reagent grade. Water, deionized. n-Butyl alcohol, for internal standard. Methanol, distilled in glass. 50% methanol in water (v/v). Calibration stock solution.



See Special Precautions

1. Sampler: 150 mg/75 mg sulfuric acid coated (20/40 mesh) silica gel tube. See Appendix for instruction on preparation. (Tubes are commercially available, but have a designated shelf life). 2. Personal sampling pump, 0.01 to 1 L/min, with flexible polyethylene or PTFE tubing. 3. Hygrometer or other suitable device for measuring relative humidity. 4. Vials, glass, 2-mL with PTFE-lined caps. 5. Gas chromatograph with a flame ionization detector, recorder, integrator and column (page 2012-1). 6. Tweezers. 7. Syringes, 10- and 500-µL. 8. Volumetric flasks, 10-mL. 9. Pipets, 1- and 10-mL glass, delivery, with pipet bulb.

SPECIAL PRECAUTIONS: Butylamine vapor can cause irritation to the eyes, nose, and throat. Inhalation can cause headache and flushing of skin. Contact with the liquid may produce severe injury to eyes and skin [4]. Potassium hydroxide is a strong caustic, corrosive to tissue. Handle with gloves. Work in a hood.

SAMPLING: 1. 2. 3. 4. 5. 6.

Calibrate each personal sampling pump with a representative sampler in line. Break the ends of the silica gel tube immediately prior to sampling. Attach outlet of tube to the sampling pump with flexible tubing. Sample 2 to 100 L of air at an accurately known flow rate in the range 0.01 to 1.0 L/min. The temperature, pressure, and relative humidity of the atmosphere being sampled should be recorded. Cap and seal the sample tube for shipment and place in a suitable container in order to prevent damage during transit. Collect a bulk sample (ca. 1 g) in a glass vial and ship it separately.

SAMPLE PREPARATION: 7. 8. 9.

Place the front and back sorbent sections of the sampler tube in separate vials. Add the glass wool plug to the front sorbent section's vial. Add 1 mL 50% methanol to the vial. Tightly cap the vial. Agitate the vial for 2 hours. Neutralization of the sample solution. Allow the silica gel particles to settle. Transfer a 500 µL aliquot to a clean vial and add 500 µL of 1.0 N KOH. NOTE 1: If the internal standard is to be used, add the internal standard solution made up in 1.0 N KOH. NOTE 2: Analyze samples immediately to avoid loss of amine as free base.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94