ISO 10370 Petroleum products - Determination of carbon residue - Micro method
WARNING - The use of this International Standard may involve hazardous materials, operations, and equipment. This International Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this International Standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1 Scope
This International Standard specifies a method for the determination of the amount of carbon residue, in the range 0.10 % (m/m) to 30.0 % (m/m), left after evaporation and pyrolysis of petroleum products under specified conditions.
NOTE 1 The carbon residue value serves as an approximation of the tendency of petroleum products to form carbonaceous deposits under similar degradation conditions, and may be useful in the assessment of relative carbon-forming tendencies of products within the same class. In this case, care should be taken in the interpretation of results.
For products which yield a residue in excess of 0.10 % (m/m), the test results are equivalent to those obtained by the Conradson carbon residue test (see ISO 6615) in the range of 0.10 (m/m) to 25.0 (m/m) (for details see Annex A).
This International Standard is also applicable to petroleum products which consist essentially of distillate material, and which may yield a carbon residue below 0.10 % (m/m). On such materials, a 10 % (V/V) distillation residue is prepared by the procedure described in 7.3.1 and 7.3.2 before analysis. Both ash-forming constituents, as defined by ISO 6245 and non-volatile additives present in the sample add to the carbon residue value and are included in the total value reported.
NOTE 2 The presence of organic nitrates incorporated in certain distillate fuels will yield abnormally high values for the carbon residue. The presence of alkyl nitrate in the fuel may be detected by ISO 13759.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3405, Petroleum products - Determination of distillation characteristics
3 Terms and definitions
For the purposes of this document, the following term and definition apply
3.1 carbon residue
the whole residue produced of a sample from the specific conditions of evaporation and pyrolysis described in this International Standard.
4 Principle
A weighed aliquot of the oil sample is placed in a glass vial and heated to 500 °C under an inert (nitrogen) gas stream in a controlled manner for a specific time. Volatiles formed during the reactions are swept away by the inert gas. The carbonaceous residue remaining is weighed.
