METHYLCYCLOHEXANONE
CH3C6H9(=0) (3 isomers)
MW: 112.17
METHOD: 2521, Issue 2
CAS: 1331-22-2
EVALUATION:
OSHA : 100 ppm (skin) (2-methyl isomer) NIOSH: 50 ppm (skin); STEL 75 ppm (2-methyl isomer) (1 ppm = 4.59 mg/m 3 @ NTP) ACGIH: 50 ppm (skin); STEL 75 ppm (2-methyl isomer) (1 ppm = 4.59 mg/m 3 @ NTP)
2521
RTECS: GW1575000
FULL
PROPERTIES:
Issue 1: 15 May 1985 Issue 2: 15 August 1994
Isomer 2-CH 3C 6H 9O 3-CH 3C 6H 9O 4-CH 3C 6H 9O
BP, °C 165 169 170
d, g/mL @ 20 °C 0.925 0.914 0.914
SYNONYMS: Isomers: 2-methylcyclohexanone; CAS #583-60-8. 3-methylcyclohexanone; CAS #591-24-2. 4-methylcyclohexanone; CAS #589-92-4. Mixture of isomers: CAS #1331-22-2. SAMPLING SAMPLER:
SOLID SORBENT TUBE (Porapak Q, 150 mg/75 mg)
FLOW RATE:
0.01 to 0.05 L/min
VOL-MIN: -MAX:
1 L @ 460 mg/m 3 6L
SHIPMENT:
routine
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, FID
ANALYTE:
3- and 4-methylcyclohexanone
DESORPTION:
1 mL acetone; stand 15 min
INJECTION VOLUME:
5 µL
SAMPLE STABILITY:
≥ 7 days @ 25 °C [1]
TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:
BLANKS:
2 to 10 field blanks per set
CARRIER GAS:
N 2, 30 mL/min
COLUMN:
stainless steel, 1.2 m x 3-mm OD, packed with 50/80 mesh Porapak Q
CALIBRATION:
standard solutions of 3- and 4- methylcyclohexanone isomers in acetone
RANGE:
0.5 to 4 mg per sample
ACCURACY RANGE STUDIED:
213 to 852 mg/m 3 [1] (3-L samples)
BIAS:
0.69%
200 °C 260 °C 190 °C
ESTIMATED LOD: 0.09 mg [1]
ˆ ): 0.057 [1] OVERALL PRECISION (S rT ACCURACY:
± 11.35%
PRECISION (Sr):
0.041 @ 0.7 to 2.9 mg per sample [1]
APPLICABILITY: The working range is 100 to 800 mg/m 3 (20 to 170 ppm) for a 5-L air sample. This method was developed for the 3- and 4-methylcyclohexanones. 2-Methylcyclohexanone is not of major commercial importance and has not been test ed with this method. The use of a capillary column would give better sensitivity; however, all the isomers may not elute as a single peak.
INTERFERENCES: None reported.
OTHER METHODS: This revises Method S375 [2].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
