Peptization 1816 INDEX

Many attempts have been made to characterize the stabiUty of the colloidal state of asphalt at ordinary temperature on the basis of chemical analysis in generic groups. For example, a colloidal instabiUty index has been defined as the ratio of the sum of the amounts in asphaltenes and flocculants (saturated oils) to the sum of the amounts in peptizers (resins) and solvents (aromatic oils) (66) ... 

Properties Colorless liq. mild nonmercaptan odor sol. in hydrocarbons insol. in water dens. 0.983 f.p. -4 C b.p. 250 C ref. index 1.546 Precaution Combustible Uses Peptizing agent in food-contact rubber articles for repeated use polymer modifier lubricating oil additive Reguiatory FDA 21CFR 177.2600... 

There are no standard tests for measuring the onset of asphaltenes precipitation. Among the techniques and analytical methods frequently used to measure sediment and asphaltenes onset for the adjustment of different process parameters in the refineries are spot test (ASTM-D-4740-95) total sediment (ASTM-4870-96) solubility parameters, optical microscope light scattering (PORLA) peptization value (P-value) ° colloidal instability index (CII) coking index. ... 

Reconstruction, of surface, 580 Redispersion, 248, 250. See also Peptization, Stability of sols Redistribution. See Reconstruction, of surface. Restructuring Reduced time, 678, 685, 688-689, 696 Reduction, 289 Reedmergnerite, 780 Reesterification. See Esterification Refractive index, 275, 465, 594 film, 790, 852 graded, 844-847 of partially sintered gels, 768 of silica, 766-767 of strontium silicate, 777, 779 silica xerogels, 581, 583... 

Colloidal instability index (CII). This index expresses the stability of asphaltenes in terms of SARA (Saturates, Aromatics, Resins, Asphaltenes) fractions and is defined as the mass ratio between the sum of asphaltenes and unfavorable components of its stability in the oil, i.e., its flocculants (Saturates) and the sum of peptizing agents (aromatics and resins), which are components favorable to the stability of asphaltenes present in a specific oil (Asomaning, 2003) ... 

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