1,1-difluoroethane (R-152) analysis using 7820A

Hi NPXone, 

I'm not sure what inlets/detectors you have on your 7820A, but based on your description of the current analysis, I'm going to assume an FID is present.  It is possible to analyze R-152 on a 7820A system.  However, there are many options that make this analysis possible.  We need to narrow down the options for best results.  

• 1st question - what will your sample look like?  R-152 is a gas, so it will need to be captured in something to contain it until it can be analyzed.  Common options are headspace vials, Tedlar bags, canisters or sorbent tubes.  
• 2nd question - what concentration ranges are you looking at?  
• 3rd question - how many samples do you plan to run in a day?  Are you seeking automation for higher throughput, or do you have the occasional sample to run?  

This analysis often incorporates a gas sampling valve, but if your sample is delivered in some sort of container that can be pierced and a sample extracted with a syringe (gas-tight), you may find success with a manual injection and an appropriate column (usually a PLOT column).  The calibration standard is usually in the form of a gas cylinder, which can be easily interfaced to a gas sampling valve.  Availability will vary with geography, so I would advise to do a web search for R-152 gas standard to see what products are available.  

I would start a search for R-152 regulations GC Analysis to get an idea of how the government methods are written and what kind of detection levels they expect.  If you are in the US, the California Air Resources Board might be a good place to start.  

Keep us posted on your progress!

Abbey

My knowledge of GCs is extremely limited. Currently we analyze for n-pentane only. The program was already set-up when I started working here.

Yes, an FID is present

1. Sampling vessel type unknown at this time.

2. I am expecting the range to be less than 0.1%; probably much lower.

3. At max, we will only run 5 samples per day. This is a special project and should last less than 3 months. An auto sampler is NOT needed.

Thanks.

Barry Bryan

NPXOne, Environmental Specialist