Design Construction of an Atmospheric Chamber for the Qualitative Study of an Unknown Compound Generated by the Photochemical Reaction Between Isoprene and NOx

Abstract

Design and construction of a 1000L atmospheric chamber was completed at Western Michigan University for the purpose of qualitative analysis of an unknown compound generated by the photochemical reaction between NOx and isoprene. Preliminary results show a fair amount of experimental reproducibility in the overall reaction pathways of the binary system. Qualitative analysis utilized GC/MS. Once the compound was generated in the chamber a sample was cryogenically trapped onto a section of GC column and taken to the GC/MS. To date, the qualitative analysis of the unknown has been unsuccessful due to difficulty in sample transportation. However, these results show that the compound may be formed from methylvinylketone and because of its behavior on the gas chromatograph columns it is suspected to be another PAN compound. Its stability also suggests that it may be a form of PAN with an OH group attached. Overall, further investigation is needed and improvement in the cryogenic trapping and transportation of the sample from the chamber to the GC/MS must be made in order to get a structural model of the unknown compound.