ASTM E1510-95(2013)e1

Заменен

Standard Practice for Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs — 13 стр.

Значение и использование

5.1 This practice is intended to be used by all analysts using fused silica capillary chromatography. It contains the recommended steps for installation, preparation, proper installation, and continued column maintenance.

Область применения

1.1 This practice covers the installation and maintenance of fused silica capillary columns in gas chromatographs that are already retrofitted for their use. This practice excludes information on:

1.1.1 Injection techniques.

1.1.2 Column selection.

1.1.3 Data acquisition.

1.1.4 System troubleshooting and maintenance.

1.2 For additional information on gas chromatography, please refer to Practice E260. For specific precautions, see 7.2.2.2(1), 7.2.2.2(2), 7.2.7, and 7.2.7.2.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific safety information, see Section 6, 7.2.2.2(1), 7.2.2.2(2), 7.2.7, and 7.2.7.2.²

TABLE 1 Typical Splitter Vent Flow Rates (50 to 1 split ratio) (at optimum linear velocity)

Carrier gas

0.25-mm ID,
cm³ /min

0.32-mm ID,
cm³ /min

0.53-mm ID,
cm³ /min

helium
hydrogen

35
70

80
160

125
250

Note 1—The curves were generated by plotting the height equivalent to a theoretical plate (length of column divided by the total number of theoretical plates, H.E.T.P.) against the column's average linear velocity. The lowest point on the curve indicates the carrier gas velocity in which the highest column efficiency is reached.Note 2—Gases information available from Compressed Gas Association (CGA), 4221 Walney Rd., 5th Floor, Chantilly, VA 20151-2923, http://www.cganet.com.FIG. 1 Van Deemter Profile for Hydrogen, Helium, and Nitrogen Carrier Gases

Carrier gas: Hydrogen

Carrier gas: Helium

Linear velocity: 40 cm/s

Linear velocity: 20 cm/s

Note 1—Fig. 2 shows that the resolution is similar but the analysis time is reduced by 50 % when comparing hydrogen to helium in an isothermal analysis using optimum flow velocities.Note 2—Hydrogen provides similar resolution in one-half the analysis time of helium for an isothermal analysis.Note 3—

1. Tetrachloro-m-

8. Heptachlor epoxide

15. Endosulfan II

xylene

9. γ-chlordane

16. DDD

2. α-BHC

10. Endosulfan I

17. Endrin aldehyde

3. β-BHC

11. α-chlordane

18. Endosulfan sulfate

4. γ-BHC

12. Dieldrin

19. DDT

5. δ-BHC

13. DDE

20. Endrin ketone

6. Heptachlor

14. Endrin

21. Methyoxychlor

7. Aldrin

Note 4—30 m, 0.25-mm ID, 0.25 μm 5 % diphenyl − 95 % dimethyl polysiloxane 0.1-μL split injection of chlorinated pesticides.

Oven temperature: 210°C isothermal

Injector and detector temperature: 250°C/300°C

ECD sensitivity: 512 × 10⁻¹¹

Split vent: 100 cm³ /min

FIG. 2 Hydrogen Versus Helium (Isothermal Analysis)
FIG. 3 Capping Silanol Groups with Dimethyl Dichlorosilane (DMDCS)
Note 1—Septum bleed can obscure or co-elute with compounds of interest, thus decreasing the analytical accuracy.Note 2—

1. 2,4,5,6-tetrachloro-

8. Heptachlor

16. p,p-DDD

m-xylene (IS)

epoxide

17. Endrin aldehyde

2. α-BHC

9. γ-chlordane

18. Endosulfan sul-

3. β-BHC

10. Endosulfan I

fate

4. γ-BHC

11. α-chlordane

19. p,p-DDT

5. δ-BHC

12. Dieldrin

20. Endrin ketone

6. Heptachlor

13. p,p-DDE

21. Methyoxychlor

7. Aldrin

14. Endrin

22. Decachlorobi-

15. Endosulfan II

phenyl (IS)

Note 3—30 m, 0.53-mm ID, 0.50 μm 5 % diphenyl − 95 % dimethyl polysiloxane 0.1 μL direct injection of 50 pg pesticide standard.

Oven temperature: 150 to 275°C at 4°C/min,
hold 15 min

Injector temperature: 250°C

Detector temperature: 300°C

Carrier gas: Helium

Linear velocity: 40 cm/s (Flow rate: 10 cm³ /min)

ECD sensitivity: 8 × 10⁻¹¹ AFS

FIG. 4 ECD Septum Bleed

Заменен на

ASTM E1510-95(2021)

ICS

71.040.50 Physicochemical. Including spectrophotometric and chromatographic analysis / Физико-химические методы анализа. Включая спектрофотометрический и хроматографический анализы

Сборник ASTM

03.06 Molecular Spectroscopy and Separation Science; Surface Analysis / Молекулярная спектроскопия; Анализ поверхности

Тематика

Spectroscopy