FROG-4000 BTEX Analysis

™Defiant Technologies Inc. 6814A Academy Parkway West NE Albuquerque, NM 87109-4406 Phone: 505-999-5880 x26 www.defiant-tech.com ajtrujillo@defiant-tech.com Authors: Amanda J. Trujillo, Douglas R. Adkins, Allister B. Hamilton, Patrick R. Lewis Monitoring ground water for volatile organic compounds (VOCs) that result from spills or leaks from industrial processes costs millions of dollars annually. Government and industry are in need of cost effective sensors to detect and monitor chemical contaminants including VOCs on a long-term basis. Defiant Technologies has developed a hand held portable system for detection of Benzene, Toluene, Ethylbenzene, Xylenes (BTEX) and other VOCs in water. The system uses a micro preconcentrator, a micro gas chromatographic column (GC) and miniature photoionization detector (PID). The micro preconcentrator has an integrated heater that desorbs the sample to the GC column. Target analytes are detected by the miniature PID. Defiant’s micro GC easily separates the major components of BTEX in under 5 minutes. This system is completely analogous to a bench top purge and trap- GC/PID. The GC column integrated heater enables temperature ramping to quickly remove late eluting compounds so that the system is ready for consecutive analyses. Testing was conducted on the FROG-4000™ system to demonstrate its ability to produce data that meets the analytical proficiency standards set forth by the EPA. The standards includes a quality control set, method detection limit study, and a blind sample test. The results show that the FROG-4000 is equivalent to a bench top purge and trap- GC/PID. y = 2673x - 7795y = 3234.6x + 27136y = 0.0003x - 0.9191y = 3748.8x - 20063y = 2577.2x - 131410501001502002500 200000 400000 600000 800000Concentration (ppb)Peak HeightBTEX - Peak Area CalibrationBenzeneTolueneEthylbenzenep/m Xyleneo XyleneR = 0.9997R = 0.9995R = 0.9987R = 0.9984R = 0.9980Continuing Calibration Verification (CCV) Benzene Toluene Ethylbenzene p/m-Xylene 0-Xylene Retention Time (sec) 50.13 103.17 215.55 232.40 275.89 Peak Area 103227 143850 132035 285480 94113 Actual Concentration (µg/L) 40 40 40 80 40 Calculated Concentration (µg/L) 41.55 36.15 40.87 81.63 41.69 % Recovery 104% 90% 102% 102% 104% Blind Sample Benzene Toluene Ethylbenzene p/m-Xylene 0-Xylene Retention Time (sec) 51.21 105.24 219.12 237.13 280.46 Peak Area 47612 254422 96824 266321 80440 Actual Concentration (µg/L) 22.1 70.4 32.1 84.3 36.3 Calculated Concentration (µg/L) 20.75 70.24 29.72 76.54 36.41 % Recovery 94% 100% 93% 91% 92% Lab Controlled Sample (LCS) Benzene Toluene Ethylbenzene p/m-Xylene 0-Xylene Retention Time (sec) 51.87 103.98 223.60 241.03 285.85 Peak Area 102101 1475478 126286 265345 82081 Actual Concentration (µg/L) 40 40 40 80 40 Calculated Concentration (µg/L) 41.13 37.29 39.05 76.28 37.04 % Recovery 103% 93% 98% 95% 93% Lab Controlled Sample Duplicate (LCSD) Benzene Toluene Ethylbenzene p/m-Xylene 0-Xylene Retention Time (sec) 51.79 106.66 223.02 240.53 285.35 Peak Area 94924 156954 118547 245800 76265 Actual Concentration (µg/L) 40 40 40 80 40 Calculated Concentration (µg/L) 38.44 40.19 36.60 71.08 34.79 % Recovery 96% 100% 91% 89% 87% Method Detection Limit (MDL) Benzene Toluene Ethylbenzene p/m-Xylene 0-Xylene Average (µg/L) 0.9950 1.1383 0.9002 0.8566 0.6331 Standard Deviation (µg/L) 0.0469 0.0917 0.1382 0.1552 0.1197 % RSD 5% 8% 15% 18% 19% Calculated MDL (µg/L) 0.15 0.29 0.43 0.49 0.38 Retention Time Statistics Benzene Toluene Ethylbenzene p/m-Xylene 0-Xylene Average (sec) 51.56 106.12 221.28 238.56 282.88 Standard Deviation (sec) 0.22 0.38 0.72 0.91 0.075 % RSD 0.42% 0.36% 0.33% 0.38% 0.27% VOCs Sample Sparger Load Sample Micro-GC PID-Detector Bypass Line Bypass Valve Preconcentrator Mole Sieves Activated Charcoal Benzene 51.21 Toluene 105.49 Ethylbenzene 220.03 p/m-Xylene 238.71 0-Xylene 283.28 BTEX 100/200ppb 32.50 23.82 Instrument Response 10000000 8000000 6000000 4000000 2000000 -2000000 0 Time (sec)