n-BUTYL MERCAPTAN
CH3CH2CH2CH2SH
MW: 90.19
METHOD: 2525, Issue 2
2525
CAS: 109-79-5
RTECS: EK6300000
EVALUATION: FULL
OSHA: 0.5 ppm NIOSH: C 0.5 ppm ACGIH: 0.5 ppm (1 ppm = 3.69 mg/m3 @ NTP)
Issue 1: 5 May 1989 Issue 2: 15 May 1996
PROPERTIES: liquid; d 0.842 g/mL @ 25 C; BP 98 C; VP 4.7 kPa (35 mm Hg; 4.6% v/v) @ 20 C
SYNONYMS: butanethiol; 1-butanethiol; 1-mercaptobutane SAMPLING
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, FPD SULFUR MODE
FLOW RATE: 0.01 to 0.05 L/min
ANALYTE:
n-butyl mercaptan
VOL-MIN: -MAX:
1L 4L
DESORPTION:
1 mL acetone; stand 15 min
SHIPMENT:
routine
SAMPLER:
SOLID SORBENT TUBE (Chromosorb 104, 150 mg/75 mg)
INJECTION VOLUME:
5 µL 150 C 200 C 140 C
SAMPLE STABILITY:
at least 7 days @ 25 C [1]
TEMPERATURE-INJECTOR: -DETECTOR: -COLUMN:
BLANKS:
2 to 10 field blanks per set
COLUMN:
glass, 1.2 m x 2-mm ID, packed with 60/80 mesh Chromosorb 104
CARRIER GAS:
N2, 50 mL/min
CALIBRATION:
standard solutions of n-butylmercaptan in acetone
RANGE:
20 to 200 µg per sample [2]
ACCURACY RANGE STUDIED: 17 to 74 mg/m3 [1] (1.5-L samples) BIAS:
- 2% [1] ESTIMATED LOD: 3 µg per sample [1]
OVERALL PRECISION ( ACCURACY:
rT):
PRECISION ( r):
0.062 [1]
0.015 @ 30 to 110 µg per sample [1]
± 14.2%
APPLICABILITY:The working range is 5 to 50 mg/m3 (1.4 to 14 ppm) maximum sample size is based on the capacity of the Chromosorb 104 to collect vapors of n-butyl mercaptan in air at high relative humidity (94%) [1]. Smaller concentrations may be determined if desorption efficiency is adequate.
INTERFERENCES:None identified.
OTHER METHODS:This revises NIOSH Method S350 [2].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 5/15/96
