Cosmo APD-500A Asphaltene Analyzer
The APD-500A utilizes a dual wavelength spectrophotometer to determine asphaltene (n-heptane insoluble) fractions of petroleum residual oils 50 times faster than conventional methods.  This rapid, fully automatic determination offers high accuracy, ease of use and significant cost savings.

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APD-500A
Fully Automatic Asphaltene Analyzer
A sample is dissolved with the addition of 1ml of toluene, to which 100ml of n-heptane at 80oC is added.  The n-heptane addition causes asphaltene particles to precipitate.

The absorbances of the solution are measured at 750nm and 850nm.  The absorbance due to asphaltene particles is calculated from the ratio of absorbances of the two wavelengths.  The asphaltene concentration is then determined from the calibration curve for asphaltene and the amount of sample.

This method has proven to show excellent correlation to ASTM and IP methods.  Correlation coefficients greater than 0.995 (APD-500A vs. ASTM) are achieved along with improved accuracy.
 

Click here for the APD-500A brochure