Friday, December 30, 2011

Application of the Photo Ionization Detector for the Single Determination of Hydride Forming Elements #hydrides#As_Sb_Sn_Se#ppb#photoionization#PID

An HNU photoionization detector PI52-02 was used to determine the detection limits of the following elements by hydride generation: arsenic, antimony, selenium, tin, sulfide, tellurium, bismuth, and ammonia. Detection limits were in the low ppb levels for arsenic to tin and sulfide compounds. Low ppm detection limits were obtained for tellurium through ammonia.


Application of the Photo Ionization Detector for the Single Determination of Hydride Forming Elements

Monday, December 26, 2011

Review of PID Apps in Industrial Hygiene #PID#GC_PID#photoionization#AIHA

This is an oldie but goodie paper on GC/PID applications in industrial hygiene.

Review of PID Apps in Industrial Hygiene

Monday, December 19, 2011

Derivitization of Drugs and Bio Organics by GC PID#PID#photoionization#GC_PID #Drugs#Bioorganics

This paper describes a method of improving the sensitivity of drugs and bioorganics by GC/PID.


Derivitization of Drugs and Bio Organics by GC PID

EPA Superfund Program Groundwater and Sediment Monitoring Guidance#EPA#Superfund#PID#Photoionization#GC/PID#water_sediment#VOC's

This program was developed for monitoring the cleanup of superfund sites.


EPA Sperfunnd Program Groundwater and Sediment Monitoring Guidande

Sunday, November 27, 2011

Analysis of Charcoal Tube Samples for Carbon Disulfide Using a Photo Ionization Detector,#Carbon_Disulfide_(CS2),#photoionization_PID,PID_analyzers,#AIHA

Carbon disulfide is detected @ 0.1 ppm with a 10L air sample (well below the OSHA PEL of 20 ppm) by charcoal tube collection follower by analysis by GC/PID.


Analysis of Charcoal Tube Samples for Carbon Disulfide Using a Photo Ionization Detector

Wednesday, November 9, 2011

Determination of Arsenic and Antimony Using Selective Hydride Generation and GC PID,#NSF,#Arsenic_in_water, #Antimony_in_water, #GC_PID

This paper uses an HNU (PID Analyzers) Model GC321 with a PID and selective hydride generation to measure arsenic and antimony species in water


Determination of Arsenic and Antimony Using Selective Hydride Generation and GC PID

Measurement of Arsenic in Sea Water by GC PID, #Arsenic_in_Sea_Water, #Knorr,#NSF,#GC_PID,#Arsenic_speciation,#WHOI

Measurement of Arsenic in Sea Water by GC PID, #Arsenic_in_Sea_Water, #Knorr,#NSF,@GC_PID,#Arsenic_speciati...

Testing of Chemical Warfare Agents via GD-PID,#CW-agents,#GC_PID, chemical-warfafe_agents,#PID_Analyzers.#sarin, #soman,#tabun

The testing was done at the University of Helsinki Laboratory. An HNU model GC311 with a PID (10.2 eV). The goal was to test the HNU Systems GC 311 for the verification of Chemical Warfare (CW) agents.


Materials & Methods
The CW-agents investigated in this work are listed in Table 1, The standard solutions of Model compounds were prepared in Methanol by consecutive dilutions of stock solution containing 100 ug/uL in ethyl acetate. Methanol was chosen as the solvent to eliminate a large solvent peak due to the lack of a split valve in the GC311. Methanol is not ionized by the 10.2 eV lamp.


The GC311 was equipped with a photoionization detector (10.2 eV) . The compounds were separated on a fused silica capillary column (phase NBW 311, 15M x 0.53 mm id x 1.5 um film thickness) . The injection volume varied from 2.5- 5uL. Injector/detector temperature was 200C and the oven temperature was 100 C for sarin, soman, tabun and mustard gas and 150C for Lewisite-3.

Results and Discussion.
Figures 1 & 2 show chromatograms of a standard solutions of sarin, soman, tabun and mustard gas at concentration levels of 100, 50, 4 and 1 ng. The detection limit of sarin, soman, tabun and mustard gasis about 1 ng and for mustard gas is 0.5 ng which is about 10 x better than that of the FID run at the same time. The sensitivity of the Lewisite-3 is 0.2 ng because of the 3 double bonds in that compound.





The portable GC311 has been shown to be a powerful instrument for the detection of CW-agents especially for the direct analysis of air samples. The instrument can also be used for the monitoring of incinerator exhaust gases during the destruction period of CW-agents. The analyzer could be more useful for the analysis of liquid samples if a split injector were available.
The GC311 is no longer in production but a new portable GC is available from PID Analyzers, the Model GC312.

Photo GC311 (no longer in production)


Photo GC312 (replacement for GC311)







The work in this report was done with an HNU GC311 shown above. The replacement instrument described in this report is a GC312 manufactured by:

PID Analyers,LLC,
2 Washington Circle,
Sandwich, MA 02563 T 1 774 413 5281 F 1 774 413 5298
url: http://www.hnu.com
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Tuesday, October 25, 2011

Review of Photoionization Detection in Gas Chromatography: The fFrst Decade

This was the first review of the photoionization detector 10 years after it was commercialized.


Review of Photo Ionization Detection in Gas Chromatography The First Decade, #Photoionization,#PID Analyzer...

Sunday, October 16, 2011

Review of Photo Ionization Detection in Gas Chromatography: The First Decade, #Photoionization,#PID Analyzers,PID,#PID_in_ gas_chromatography

This is the first review of photoionization in gas chromatography.


Review of Photo Ionization Detection in Gas Chromatography The First Decade, #Photoionization,#PID Analyzer...

Sunday, October 9, 2011

Determination of Water & O2 at Low ppm Levels by GC-FUV

The Far UV absorbance detector that can measure low ppm levels of water and oxygen has been improved by modifying the detector design.




Determination of Water & O2 at Low Ppm Levels by GC FUV

Saturday, September 24, 2011

Capillary Gas chromatographic Analysis with the Far UV (FUV) Detector #GC,#Capillary_GC.#PID Analyzers,#FUV,#ppm,#ppb

Here is an older paper on the Far UV absorbance Detector (FUV) that is a popular download on our website. The FUV can detect water, O2, and inorganic compounds at the same time as organic compounds. at ppm to ppb levels. The FUV sensitivity has been improved and this detector has been reintroduced by
PID analyzers.


Driscoll 1988 Capillary Gas Chromatographic Analysis Withthe Far UV[1]

A schematic of the FUV detector for GC is shown below:


A chromatogram of C1 to C6 hydrocarbons on a thick film capillary column follows:

Saturday, September 17, 2011

Gas Chromatography in Environmental Analysis #PID, #photoionization, #environment, #Gas_Chromatography, #PID, #PID_Analyzers

This chapter describes gas chromatography, GC detectors, GC columns used in environmental analyses, and applications of these techniques for analysis of environmental samples.


Gas Chromatography in Environmental Analysis- Driscoll 2004 L


The work in this chapter could done with a PID Model GC312 shown above. The GC is manufactured by:
PID Analyers, LLC
2 Washington Circle
Sandwich, MA 02563
1 774 413 5281
URL: http://www.hnu.com
Blogs: follow us at:
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Tuesday, August 23, 2011

The_Use_of_Photoionization,Flameionization_and_Electron_Capture_Detector_in series_for_Low_MW_Trace_Components_in_Non_Urban_Atmospheres #photoionization, # PID, #FID, #ECD, #non urban atmospheres, #PI52, #GC, #gas chromatography

The paper below from the Institut fur Chemie in Germany compares GC- PID, FID and ECD for non urban samples that were concentrated on tenax. The PID (Model PI52) with an HNU 11.7 eV lamp compares in sensitivity with the ECD for low MW chloroalkanes. and with the FID for a number of hydrocarbons. The HNU PID with a 10.2 eV lamp is more sensitive than the FID or the PID with an 11.7 eV lamp.

The Use of Photoionization,Flameionization and Electron Capture Detector Inseries for Low MW Trace Componen...

A photo of the PID Analyzers Model PI52 is shown below:


Sunday, August 21, 2011

Far UV Ionization (Photoionization) and Absorbance Detectors for Capillary GC #gas chromatograpgy,#capillary GC, #photoionization, #Far UV Absorbance, #PID, #FUV

This is a chapter on photoionization and far UV absorbance detectors that I wrote about 20 years ago. It has been posted on our website and is a popular download:



It was published in 1992 by Wiley, is entitled " Detectors for Capillary GC" and was edited by H. Hill & D. McGinn.

The article is posted below:

Far UV Ionization Photo Ionization) and Absorbance Detectors for CapillaryGC

Sunday, August 14, 2011

GC_Detection_and_Identification_of_Hydrocarbons_by_Coupling_a_PID_and_FID

This is a paper that I wrote more than 30 years ago on the coupling of a GC PID/FID for the identification of hydrocarbons in complex mixtures. This remains one of the popular downloads on our website http://www.hnu.com . I remember calling this technique a “poor man’s mass spec” but the referee made me remove it. I still believe it though. Follow my blog at http://gcdetectors.blogspot.com, and http://gasanalysis.blogspot.com, #PID/FID, #photoionization, #pidanalyzers, #identification of hydrocarbons, #GC. #PID

HTML embed
Driscoll, JN GC Detection and Identification of Hydrocarbons by Coupling aPID and FID

Our stand alone photoionization detector (PID) was described in a previous blog:



A New PID for Trace Analysis PC2010a

Tuesday, July 26, 2011

Why do I need a PID for my laboratory?

The PID Analyzers photoionization detector (PID) is one of the most sensitive GC detectors ever developed.

Features include the following:
    Easy to use
    Sub ppb detection of aromatic hydrocarbons
    Wide dynamic range 108
    No support gases are required
    Can be used to upgrade an old GC
    Ideal to add on to a new GC
    Non destructive so a second detector can be run in-series
    Response factors for two detectors can provide identification of species
   

    The PID is used for many EPA Methods 502, 602, SW846....
     

Thursday, July 7, 2011

Measurement of ppb Levels of Gasoline in Groundwater by Portable GC-PID

Contamination of groundwater and soils by leaking underground storage tanks continues to be a serious environmental problem. Twelve  years ago, the EPA was monitoring about 370,000 leaking underground storage tank sites in the United States. Only about 5% were scheduled for site cleanups in 2001.  Cleanups are funded by the EPA's LUST Trust Fund, which was funded at a level of about $70 million per year. The University of Colorado at Boulder has summarized the information on Leaking Underground Storage Tanks at the following link:
HNU, working with Jim Stuart, Professor Emeritus, University of Connecticut, has shown that a portable GC with a photoionization (PID) is an ideal tool for analyzing gasoline samples in groundwater and soil.  The recently introduced portable GC (Model 312 see photo) has an improved PID, improved range, is more lightweight & compact, is battery operated and will run off the 12 VDC in an automobile. Thus local power requirements are not necessary.

Photo GC312 Portable GC
Aromatics are among the most hazardous components of gasoline (the EPA maximum contaminant level in drinking water is 5 ppb of benzene). The PID has a higher sensitivity to aromatics than to any other hydrocarbons making this GC-PID ideal for cleanup of gasoline contaminated sites. EPA CLP methods as outlined in SW-846 include’ Method 3810, a headspace method for VOC’s, that provides the rapid screening of large numbers of samples.

Note that the detection limits for benzene, toluene, ethylbenzene, xylenes, TCE & PCE are all at the ppt level with just a 50 mL sample injection. The PID has a dynamic range of nearly 108 . The GC312 software has a 4 point calibration so that the results can be kept linear over a wide concentration range. Some typical response curves are shown in the Figure below.
Calibration Curves for benzene and toluene
The headspace method can be performed in the same 40 mL VOA vials that samples are collected in for lab analysis. After completely filling with sample, cap the vial with a teflon faced septum. To produce the headspace, remove 10 ml of the water via a syringe (filled with clean air) while keeping the vial inverted. Shake for about 2 minutes. Remove a 25-100 mL headspace gas sample for injection into the GC.  The Table below displays the excellent results for the field headspace and the purge & trap lab GC results.

For more information on our GC312, visit our website at http://www.hnu.com  

Monday, June 27, 2011

A New PID for Trace Analysis

I have had a number of requests for copies of my paper from Pittcon 2010 entitled " A New PID for Trace Analysis". This presentation describes the 4 th generation PID which was first introduced by us at the Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy in Cleveland, OH in 1976. The 4th generation detector with improved sensitivity and lower dead volume is shown below:


4 th Generation PID

 See  presentation below.

A New PID for Trace Analysis PC2010a

Wednesday, June 8, 2011

Is a PID more sensitive than an FID?

A photoionization detector (PID) for gas chromatography (GC), with a proper design should be 50-100 times more sensitive than a flame ionization detector (FID) click on PID-FID ratios.  Some PIDs only have the same or less sensitivity than an FID. The PID Analyzers PID has a dynamic range of 10 exp 8 click on ( 4th-generation-photoionization-detector) and a detection limit of < 1 ppb of benzene   click on (ppt-levels-of-benzene-in-air-by-pid ) .  Contact us at http://www.hnu.com



Is is interesting to note that when we (HNU) introduced the 1st commercial PID in 1976 at #Pittcon in Cleveland, and we stated that  "Our PID is 50 times more sensitive than an FID for benzene", we were greated  with skepticism. Today, 35 years later, many people are still unaware that the PID has this kind of sensitivity.

Photo of PID

Saturday, April 30, 2011

ppt Levels of benzene in Air by PID-GC

A PID Analyzers Model 312 GC (http://www.hnu.com) with a photoionization detector  (PID-10.6 eV lamp) is shown below and was used to detect ppt (parts per trillion) levels of benzene in an air nitrogen mix.  A 100 ppb standard of benzene in air was diluted with prepurified nitrogen to obtain  ppt levels of benzene. A chromatogram with 500 ppt of benzene is show in the Figure below.

The column was a 30M x 0.32 mm id with a 5 micron film of methyl silicon ( http://www.vici.com/). The column flowrate was 6 cc/min of hydrogen with an additional  makeup of 6 cc/min. The temperature was isothermal at 120C.  The sample was injected with a 10 port valve that had a 0.2 cc loop.


Our PID, with a sealed window, is the most sensitive one available since ppt levels of aromatics can be detected by direct injection without preconcentration.  This detector has a very wide dynamic range of 108.

Saturday, April 16, 2011

GC Detectors: Low ppb Levels of BTEX in water by Headspace GC

GC Detectors: Low ppb Levels of BTEX in water by Headspace GC: "We have used a PID Analyzers GC312 (portable GC) with a photoionization detector (PID) http://www.hnu.com/ for analysis of VOC's in water us..."

Low ppb Levels of BTEX in water by Headspace GC

We have used a PID Analyzers GC312 (portable GC) with a photoionization detector (PID) http://www.hnu.com/ for analysis of VOC's in water using the headspace method (40 ml VOA vials). The sample injected was 0.2 cc of headspace. A 1 ppm mix of 524.2 was prepared as a standard. The BTEX compounds were identified and used as standards for analysis of unknown field samples. A 30M x 0.32 mm id with a 5 micron film of methyl silicon ( http://www.vici.com/ The chromatogram for the standard is shown below:

One of the samples containing 20 ppb of BTEX  is shown below:

The sensitivity of the method is displayed in the following sample that was found to contain 3 ppb of benzene:

This method clearly has ppt level capability by simply injecting a larger sample volume eg 1 cc instead of 0.2cc. The headspace GC method is ideal for field measurements since it  requires little incremental equipment (40 ml VOA vials, 1 cc gas tight syringe) and is easy to implement.