Alkylate Standard on Rtx-DHA 50 by Method D5134-13

GC_PC1319

	Peaks	Kovats RI @ 35 °C	D5134-13 RI Comparison	Linear RI	D5134-13 RI Comparison
1.	Isobutane	--	367.3	--	--
2.	n-Butane	400.0	400.0	--	--
3.	Isopentane	475.0	475.0	--	--
4.	n-Pentane	500.0	500.0	--	--
5.	2,3-Dimethylbutane	565.4	565.5	--	--
6.	2-Methylpentane	569.2	569.5	--	--
7.	3-Methylpentane	583.1	583.4	--	--
8.	2,4-Dimethylpentane	629.9	630.3	--	--
9.	2,2,3-Trimethylbutane	635.1	635.4	--	--
10.	2-Methylhexane	667.2	667.8	--	--
11.	2,3-Dimethylpentane	668.6	669.1	--	--
12.	3-Methylhexane	675.5	676.2	--	--
13.	2,2,4-Trimethylpentane	689.9	688.7	--	--
14.	2,2,3-Trimethylpentane/2,5-dimethylhexane	731.5*	731.9	--	--
15.	2,4-Dimethylhexane	733.2*	733.5	--	--
16.	2,3,4-Trimethylpentane	747.1*	747.8	--	--

	Peaks	Kovats RI @ 35 °C	D5134-13 RI Comparison	Linear RI	D5134-13 RI Comparison
17.	2,3,3-Trimethylpentane	750.0*	751.1	730.4*	730.2
18.	2,3-Dimethylhexane	--	--	744.4*	743.6
19.	2-Methylheptane	--	--	754.0*	754.1
20.	4-Methylheptane/3,4-dimethylhexane (isomer)	--	--	756.3*	756.0
21.	3,4-Dimethylhexane (isomer)	--	--	763.6*	763.4
22.	3-Methylheptane	--	--	754.0*	754.1
23.	2,2,5-Trimethylhexane	--	--	779.7*	778.8
24.	2,2,4-Trimethylhexane	--	--	786.4*	785.1
25.	2,4,4-Trimethylhexane	--	--	805.4	805.7
26.	2,3,5-Trimethylhexane	--	--	817.4	817.7
27.	2,4-Dimethylheptane	--	--	826.1	826.6
28.	2,6-Dimethylheptane	--	--	833.4	833.8
29.	2,5-Dimethylheptane	--	--	839.9	840.3
30.	2,3,4-Trimethylhexane	--	--	849.7	--
31.	2,3-Dimethylheptane	--	--	860.0	860.4
32.	2,4,6-Trimethylheptane	--	--	878.6	--

*Extrapolated from n-C6 and n-C7 or from n-C8 and n-C9

Injection
Column	Rtx-DHA-50, 50 m, 0.20 mm ID, 0.50 µm (cat.# 10147)
Standard/Sample	ASTM D5134 qualitative reference alkylate standard (DCG Partnership I, LTD)
Inj. Vol.:	0.2 µL split (split ratio 200:1)
Liner:	Premium 4.0 mm ID Precision inlet liner w/ wool (cat.# 23305.5)
Inj. Temp.:	200 °C
Oven
Oven Temp.:	35 °C (hold 30 min) to 200 °C at 2 °C/min
Carrier Gas	He, constant pressure
Linear Velocity:	23 cm/sec

Detector	FID @ 250 °C
Make-up Gas Flow Rate:	30 mL/min
Make-up Gas Type:	N₂
Hydrogen flow:	40 mL/min
Air flow:	370 mL/min
Instrument	Agilent 7890B GC
Notes	Understanding the hydrocarbon components in petroleum samples is useful for sample characterization, determining product quality, planning and modeling of refinery processes, and also for regulatory purposes. ASTM D5134-13 provides the composition of paraffin, naphthenes, and monoaromatic compounds up to n-C9 in petroleum naphthas, reformates, and alkalytes. This method is run using a long, narrow-bore column, which has a limited sample loading capacity. Therefore, high split is used and a small sample volume is injected. Restek’s Rtx-DHA-50 column is a good match for this analysis; retention index (RI) data are in agreement with the RI data provided in the method.

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