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What is the relationship between smoke point and ASTM D-86 of kerosene? Does an increase in IBP increase the smoke point or is it the increase in final boiling that increases the smoke point?
 
Answers
30/06/2012 A: Lionel SHEIKBOUDHOU, Sara, lionel.sheikboudhou@gmail.com
Just to fix ideas in case the OP wonders why more aromatics means lower smoke point...
Aromatics (contains unsaturated benzene rings) have higher carbon-to-hydrogen ratio. And this is that deficiency of hydrogen that can cause unburned HC (smoke) during combustion in a Jet engine.
More aromatics means lower smoke point (low is bad).
02/07/2010 A: RAUL FLORES, PDVSA INTEVEP, fraulf@hotmail.com
Highest the FBP, poorest the Smoke Point but that depends on the molecularity of the FBP. Remember that the ASTM D 1655 – 09 establish a minimum Smoke point of 25 mm, or a minimum of 18 mm and a Naphthalene content of 3.0 vol, % maximum. Naphthalene is located at the FBP tail.
23/02/2010 A: omsakhti kesavan, GFPC, sakthikesavan@gmail.com
Smoke point is directly related to the Aromatic, if you done more aromatic saturation, then the smoke point will increase.
04/02/2010 A: Morgan Rodwell, Fluor Canada Limited, morgan.rodwell@fluor.com
A good simple correlation to estimate smoke point from TBP and gravity data is probably that published by (Albahri, T. A., Riazi, M. R., Alqattan, A. A., "Analysis of Quality of the Petroleum Fuel," Energy & Fuels, 2003, Vol. 17, pp. 689-693.). The relationship therein is that increasing API gravity and Mean Average Boiling Point increase the smoke point. So increasing your IBP or FBP may reduce API gravity more than the benefit of adjusting the MeABP, which might reduce the smoke point.
Mr. Ragsdale is correct that increasing the FBP is more likely to increase the aromatics content, which is bad for smoke point.
04/02/2010 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
I assume this is after hydrotreating, in which case olefins are not the culprit, and aromatics are. If the aromatics are more concentrated at the FBP, then cutting back will help. Of course, more severe hydrotreating would help as well.