5.1 This procedure describes a rapid and sensitive method for measuring the visible spectrum of asphaltenes in crude oils and petroleum products containing residual material using a microfluidic technique.

5.2 The method is sensitive to small changes in concentration of asphaltenes. Therefore, it can be used as a quality control and chain-of-custody check for fuel or crude oil samples.

5.3 The visible spectrum of asphaltenes obtained using this technique is correlated to the mass concentration of asphaltenes using conventional gravimetric techniques (see X1.3.3).

5.4 This test method can be used by refiners as well as upstream laboratories. The test is intended for samples with asphaltenes content less than 15 % by mass.

1.1 This test method covers the measurement, either in the laboratory or in the field, of visible spectra of asphaltenes and maltenes in gas oil, diesel fuel, fuel oils, residual fuel oils, lubricating oil, bitumen, and crude oil using microfluidics and spectrographic techniques.2

1.2 These measurements can be related quantitatively to the mass percent of asphaltenes present in the sample.

1.3 The test method is limited to asphaltene-containing oil with asphaltenes content less than 15 % by mass.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.