USEPA Methods 8270 and 8260 on a Single GCMS Without Changing Columns

Transcription

1 USEPA Methods 8270 and 8260 on a Single GCMS Without Changing Columns Richard Whitney, Laura Chambers, Clifford Taylor Shimadzu Scientific Instruments, Inc. Columbia, MD Spotlight on Method 8270 Instrumentation

2 Venting the MS to... USEPA Methods 8270 and 8260 on a Single GCMS Without Change Columns Richard Whitney, Laura Chambers, Clifford Taylor Shimadzu Scientific Instruments, Inc. Columbia, MD Spotlight on Method 8270 Instrumentation

3 Problem Small laboratory Limited budget Multiple applications No time The Big Bang Theory CBS.com 3

4 Solution 8260 and 8270 Single GCMS Two inlets, two columns No venting The Big Bang Theory CBS.com 4

5 What We Did Instrument configuration Optimize method parameters Analytical results (aka data) 5

6 Instrument Configuration 6 GCMS-QP2010 SE Production Workhorse

7 Instrument Configuration 7 GCMS-QP2010 SE Production Workhorse

8 Instrument Configuration (cont.) GCMS Twin Line Kit 8

9 Instrument Configuration (cont.) 9

10 Instrument Configuration (cont.) 10

11 Instrument Configuration (cont.) 58 L/sec (He) Pfeiffer TMP (Rotary pump 30 L/min) 11

12 Instrument Configuration (cont.) 12

13 Instrument Configuration (cont.) Ecology Mode saves ~26% 13

14 Instrument Configuration (cont.) Parameter EPA Method 8260 EPA Method 8270 Sample introduction Purge-and-trap Liquid syringe Liner Shimadzu multi-purpose split liner, no glass wool Shimadzu multi-purpose split liner, no glass wool Injection conditions Split 75:1 Split 10:1 Column Maximum column temperature Carrier gas MS pump Rxi-624Sil MS 20 m x 0.18 mm x 1.4 µm Rxi-5Sil MS 20 m x 0.18 mm x 0.18 µm Program = 320 C Program = 350 C Helium, constant linear velocity mode Single stage TMP, max flow 4 ml/min (He) MS interface 225 C Ion source EI, 200 C 14

15 Instrument Configuration (cont.) Born in Kyoto Made in the USA 15

16 Method Optimization Primary objectives 1. Keep total column flow rate below 4 ml/minute 2. Keep maximum oven temperature below 320 C 3. Keep GC run time as short as practical The Big Bang Theory CBS.com 16

17 Method Optimization (cont.) Parameter Column constant linear velocity Method 8260 Primary 45 cm/second ~0.8 ml/min Method 8270 Inactive 30 cm/second ~0.5 ml/min Maximum total column flow Oven program 35 C (5 min) 20 C/min to 220 C (hold 2.5 min) ~1.3 ml/minute NA GC run time 12.5 minutes NA 17

18 Method Optimization (cont.) Parameter Column constant linear velocity Method 8260 Inactive 30 cm/second ~0.5 ml/min Method 8270 Primary 40 cm/second ~0.7 ml/min Maximum total column flow Oven program NA ~1.2 ml/minute 45 C (0.5 min) 25 C/min to 315 C (hold 4.2 min) GC run time NA 16 minutes 18

19 Why Constant Linear Velocity? Van Deemter Plot Optimal LV for each carrier Gas Linear Velocity Isothermal Oven 19

20 Why Constant Linear Velocity? (cont.) Head Pressure (kpa) Flow (ml/min) Linear Velocity (cm/sec) Oven Temp 20 With temperature programming: 1. Viscosity of gas increases 2. Gas expands 3. Flow rate and LV drop

21 Why Constant Linear Velocity? (cont.) Constant Pressure Linear Velocity Head Pressure Flow Linear Velocity Linear Velocity Oven Temp 21

22 Why Constant Linear Velocity? (cont.) Constant Flow Linear Velocity Head Pressure Linear Velocity Oven Temp Flow Linear Velocity 22

23 Why Constant Linear Velocity? (cont.) Constant Linear Velocity Linear Velocity Head Pressure Flow Linear Velocity Oven Temp 23

24 Why Constant Linear Velocity? (cont.) Constant Pressure Linear velocity = 15 cm/sec Constant Flow Linear velocity = 20 cm/sec Constant Linear Velocity Linear velocity = 30 cm/sec 24

25 Analytical Results BFB Spectrum EPA Method 8260 BFB Tune Criteria Passed 25

26 Analytical Results (cont.) EPA Method µg/l calibration standard TIC 66 compounds resolved 26

27 Analytical Results (cont.) DFTPP Spectrum EPA Method 8270 DFTPP Tune Criteria Passed 27

28 Analytical Results (cont.) Pentachlorophenol Benzidine Benzidine and Pentachlorophenol Tailing DDT (expanded) DDE DDD DDT Breakdown 28

29 Analytical Results (cont.) Pentachlorophenol Benzidine Benzidine and Pentachlorophenol Tailing DDT (expanded) DDE DDD DDT Breakdown 29

30 Analytical Results (cont.) EPA Method µg/ml calibration standard TIC 66 compounds resolved 30

31 Analytical Results (cont.) EPA Method 8270 Calibration Range 6 Internal Standards Response Factor Linear Curve 8 points, µg/ml Acenaphthene-d10, Cyrysene-d12, 1,4-Dichlorobenzene-d4, Naphthalene-d8, Perylene-d12, Phenanthrene-d10 40 µg/ml each 54 compounds < 15% RSD Min. RF = 0.132, Pentachlorophenol Max. RF = 3.966, bis(2-chloroisopropyl)ether 12 compounds > 15% RSD Min r = 0.997, 2,4-dinitrophenol Max r = 0.999, 8 compounds 31

32 Analytical Results (cont.) r = Nitrophenol (2 µg/ml) 32

33 Analytical Results (cont.) RSD b = 6.1% RSD k = 12.0% 33 Benzo(b&k)fluoranthenes (1 µg/ml)

34 %RSD Analytical Results (cont.) 12.0 % Relative Standard Deviation (0.4 µg/ml*, n = 8) /66 RSD < 8% 39/66 RSD < 4%

35 Average % Recovery Analytical Results (cont.) Average % Recovery (0.4 µg/ml*, n = 8) 57/66 Recovery %

36 IDL (µg/ml) Analytical Results (cont.) 0.80 Statistical Instrument Detection Limit (0.4 µg/ml, n = 8) /66 IDL < 0.2 µg/ml

37 Analytical Results (cont.) DCM carryover < 1.0 ppb 37

38 Analytical Results (cont.) Acetone carryover ~ 1.0 ppb 38

39 Summary Two methods Two intro techniques Two injection ports Two columns One MS All method criteria passed One happy customer Shimadzu application note GCMS-1302 The Big Bang Theory CBS.com 39

40 Acknowledgements Richard R. Whitney, Ph.D. Configuration insight and all the hard work! Julie Kowalski Advice re column and conditions Columns and standards 40

41 Shimadzu Scientific Instruments 41 Products People - Passion