ASTM D3238: Carbon Distribution including PLTL-85 molecular wt. by boiling point

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ASTM D3238 Calculation of Carbon Distribution and Structural Group Analysis of Petroleum Oils by the n-DM Method

Carbon distribution and ring content data are used in characterization of oils in the refining-manufacturing process and can also correlate to critical performance properties.  Refractive Index, Density and Molecular Weight (n-DM) are used to calculate the following values:

% CA Percentage of Aromatic Carbon 
% CN Percentage of Naphthenic Carbon 
% Cp Percentage of paraffinic Carbon 
RA Average Number of aromatic rings per Molecule 
RN Average Number of naphthene rings per Molecule
RT Average Number of rings per Molecule 

The mass % Sulfur must be determined in order to calculate values for RT and RN.

The n-DM and Sulfur content are determined by the following:

Refractive Index (n)  ASTM D1218 
Density at 20°C (d)  ASTM D1481
Average Molecular Weight (M) ASTM D2502
Sulfur Content (mass %) ASTM  D2622 

Applicability of the method is limited to the following:
In terms of carbon distribution – up to 75% carbon atoms in ring form; % aromatic less than or equal to 1.5 times the % naphthenic rings.
In terms of ring content – up to four rings per molecule with not more than half of them aromatic.


Price: $592.00

Sample size: 100 ml

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