Chromatography Forum

I have been using a PFPD detector for sulfur analysis. I have had a number of problems w/ my PFPD detector. After replacing a bad photomultiplier tube and a faulty channel cable. I injected small amounts of sulfur for tuning the PFPD for sulfur analysis. Soon after that I began to see a very large carbon peak that was not previously there. I replaced my column in cases the carbon peak was really from the column degrading. I have contacted OI, and they suggest that my detector needs to be cleaned and that I should send it in to them for cleaning. Does anyone know a way to clean these detectors w/ out sending it in or, at least, know a way to verify that the detector is indeed dirty?

I'm a little surprised that OI asked you to send in the detector for cleaning, there is really not much that can be cleaned. If you are getting an early emission, check the column intallation. If the column is inserted too far up, it can be heated by the flame and give an early emission signal.

As far as cleaning, there is a glass rod that acts as a light pipe, that can be cleaned with a swab moistened with solvent. The combustion tube might also be contaminated, but cleaning this is usually not very successful. I always replaced those instead of trying to clean.

as far as I know not a lot can be cleaned.just replace the combustion chamber will do. Never had any problems with this detector!