Ashing

This redirect is about the test in petroleum manufacturing. For the semiconductor manufacturing process, see plasma ashing.

Ashing is a test to deduce the amount of ash forming material present in a petroleum product so as to decide its use in certain applications. Ash-forming materials are considered to be undesirable impurities or contaminants.

The specimen is placed in a suitable vessel, evaporating dish or crucible and ignited. It is allowed to burn until only ash and carbon remains. The carbonaceous residue is reduced to ash by heating in a muffle furnace at about 775 °C, cooled and weighed.

Ashing is also performed prior to chemical analysis by inductively coupled plasma emission spectrometry. Another application is the detection of asbestos content in certain products.

See also

• Ash (analytical chemistry)
• Inductively coupled plasma emission spectrometry
• Atomic absorption spectroscopy