Record Details
Gas-liquid chromatographic determination of low molecular weight aliphatic aldehydes in diesel engine exhaust
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Gas-liquid chromatographic determination of low molecular weight aliphatic aldehydes in diesel engine exhaust |
| Names |
Anderson, Bruce Conrad
(creator) Mingle, J. G. (advisor) |
| Date Issued | 1968-10-22 (iso8601) |
| Note | Graduation date: 1969 |
| Abstract | The study of aldehydes in diesel exhaust is important because of their relationship to diesel odor, to air pollution, and to the development of a theory of combustion. Therefore, a study is made of the low order aliphatic aldehydes using gas chromatography in conjunction with standard wet chemical tests. The engine is a two stroke-cycle GMC 3-71 RC diesel, with standard injectors, connected to an eddy current dynomometer. A special ten foot insulated exhaust pipe is used for the sample collection. Engine load and exhaust pipe length are used as variables, two probes 6. 7 feet apart being sampled simultaneously. For the gas chromatographic analysis the aldehydes are converted to 2, 4-dinitrophenylhydrazone derivatives in special tall form bubblers. The precipitates are then volumetrically dissolved in carbon disulfide in preparation for the chromatographic separation. The columns are ten percent SF 96 on 60-80 mesh acid washed DMCS treated Chromosorb W in 6 feet by 0. 085 inch I. D. stainless steel. Nitrogen at 60 ml per minute is used as the carrier gas and the hydrogen flow for the flame ionization detector is 35 ml per minute. The column temperature is 230°C and the injector temperature 270°C. The sample injection size is 10μ. The chromotropic acid test is used as a wet test for the formaldehyde concentration in the exhaust, the MBTH test being used for total aliphatic aldehydes. The wet tests are used for correlation studies with the gas chromatograph and for comparison with literature values. No correlation was found between the chromatograph and wet tests, the wet tests usually giving higher values. Both tests, however, indicate the concentration of aldehydes in the exhaust increases with load. The average molecular weight of the lower molecular weight aldehydes in the diesel exhaust is found by gas chromatographic analysis to be approximately 35, 75-80 mole percent of the total aldehydes being formaldehyde. The average molecular weight decreases with probe length, as predicted by theory, and the concentration increases. |
| Genre | Thesis/Dissertation |
| Topic | Aldehydes |
| Identifier | http://hdl.handle.net/1957/46430 |
