- Method ASTM D482
- Repeatability .003 - .007 wt. %
- Reproducibility .005 - .024 wt. %
- Blending linear
- Additive Correction No
Intended for petroleum products that are free from added ash-forming additives, including certain phosphorus compounds, this test will determine ash in the range 0.001 - 0.180 mass %, from distillate and residual fuels, gas turbine fuels, lubricating oils, crude oils, waxes, and other petroleum products, in which any ash-forming materials present are typically considered undesirable impurities or contaminants.
Ash is defined as the material left over after complete sample combustion has taken place. This means that any sediment, metals, or non-combustible materials will show up as ash.
The method works by weighing a piece of sample in a ceramic crucible which has also been weighed. This crucible is then placed over a lit Bunsen burner to ignite the sample and accelerate the combustion process. Once the sample is no longer burning it is transferred to a furnace to rid the crucible of any carbon based soot let. After this the crucible is cooled and weighed to calculate the ash basis weight percent.