PAMS on Rt-Alumina BOND/MAPD (by FID) and Rxi-624Sil MS (by MS) using Deans Switch

	Peaks	t_R (min)
1.	Ethane	7.68
2.	Ethylene	8.68
3.	Propane	10.36
4.	Propylene	15.58
5.	Acetylene	17.86
6.	Isobutane	7.19
7.	trans-2-Butene	7.84
8.	n-Butane	7.94
9.	cis-2-Butene	8.19
10.	1-Butene	8.61
11.	Isopentane	10.16
12.	1-Pentene	10.99
13.	n-Pentane	11.25
14.	trans-2-Pentene	11.82
15.	Isoprene	12.22
16.	cis-2-Pentene	12.28
17.	2,2-Dimethylbutane	13.19
18.	2,3-Dimethylbutane	15.03
19.	2-Methylpentane	15.15
20.	Cyclopentane	15.28

	Peaks	t_R (min)
21.	3-Methylpentane	16.16
22.	1-Hexene	16.76
23.	n-Hexane	17.05
24.	2,4-Dimethylpentane	18.7
25.	Methylcyclopentane	18.94
26.	Bromochloromethane	19.86
27.	2-Methylhexane	20.56
28.	Cyclohexane	20.71
29.	2,3-Dimethylpentane	20.79
30.	3-Methylhexane	21
31.	Benzene	21.39
32.	2,2,4-Trimethylpentane	21.63
33.	n-Heptane	22
34.	1,4-Difluorobenzene	22.3
35.	Methylcyclohexane	23.34
36.	2,3,4-Trimethylpentane	24.12
37.	2-Methylheptane	24.46
38.	3-Methylheptane	24.75
39.	Toluene	25.41
40.	n-Octane	25.55

	Peaks	t_R (min)
41.	Chlorobenzene-d5	27.83
42.	Ethylbenzene	27.98
43.	n-Nonane	28.11
44.	m-Xylene	28.17
45.	p-Xylene	28.17
46.	o-Xylene	28.76
47.	Styrene	28.78
48.	Isopropylbenzene	29.28
49.	4-Bromofluorobenzene	29.56
50.	n-Propylbenzene	29.86
51.	1,2,3-Trimethylbenzene	29.96
52.	n-Decane	30
53.	p-Ethyltoluene	30.01
54.	1,3,5-Trimethylbenzene	30.08
55.	m-Ethyltoluene	30.37
56.	1,2,4-Trimethylbenzene	30.6
57.	o-Ethyltoluene	31.16
58.	m-Diethylbenzene	31.34
59.	p-Diethylbenzene	31.48
60.	n-Undecane	31.52
61.	n-Dodecane	32.84

Oven
Column	Rxi-624Sil MS, 60 m, 0.25 mm ID, 1.40 µm (cat.# 13869)
	with zero dead volume Valco internal union (cat.# 20150)
Standard/Sample	Ozone precursor/PAMS mix (cat.# 26370)

Diluent:	Air
Conc.:	10 ppbv
Injection	on-column
Oven Temp.:	35 °C (hold 7 min) to 60 °C at 3 °C/min to 170 °C at 10 °C/min to 250 °C at 30 °C/min (hold 6 min)
Carrier Gas	He, constant flow
Flow Rate:	2.0 mL/min

Detector

Mode:

Scan

Scan Program:

Group	Start Time (min)	Scan Range (amu)	Scan Rate (scans/sec)
1	5.7	29-226	3.7

Transfer Line Temp.:

250 °C

Analyzer Type:

Quadrupole

Source Type:

Extractor

Source Temp.:

230 °C

Quad Temp.:

150 °C

Electron Energy:

70 eV

Solvent Delay Time:

5.7 min

Tune Type:

BFB

Ionization Mode:

Preconcentrator

Markes Unity 2 + CIA

Trap 1 Settings

Cooling temp.:

5 °C

Desorb temp.:

300 °C

Desorb flow:

6 mL/min

Desorb time:

180 sec

Internal Standard

Purge flow:

50 mL/min

Purge time:

60 sec

Vol.:

50 mL

ISTD flow:

50 mL/min

Standard

Size:

400 mL

Purge flow:

50 mL/min

Purge time:

60 sec

Sample flow:

100 mL/min

Instrument

Agilent 7890B GC & 5977A MSD

Notes

Deans switch time: 6.489 min
Primary column to Deans switch: Rxi-624Sil MS 60 m x 0.25 mm x 1.40 μm (cat.# 13869), 2 mL/min He
Secondary column to FID: Rt-Alumina BOND/MAPD 30 m x 0.25 mm x 4 μm (cat.# 19781), 3 mL/min He
Transfer line to MS: intermediate-polarity deactivated 1 m x 0.1 mm (cat.# 10100), 3 mL/min He

FID Parameters
Temperature: 250 °C
H₂ flow: 30 mL/min
Air flow: 400 mL/min
Makeup (N₂) flow: 22 mL/min
Data rate: 5Hz

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