CATALYSIS OF ASPHALT OXIDATION BY MINERAL AGGREGATE SURFACES AND ASPHALT COMPONENTS

Asphalt smaples recovered from previous inverse gas liquid chromatography (IGLO) studies of asphlat-aggregate interactions were analyzed by an analytical technique (for the qualitative and quantitative measurement of the carbonyl-type compounds formed during oxidation) for possible catalytic effects during their oxidation. The asphalts and asphalt fractions were coated on particles of aggregates and on inert fluorocarbon and oxidized in an IGLC column. Oxidized samples were recovered from the aggregates. The oxidation products absorbing in the carbonyl region of the infrared spectra (ketones, dicarboxylic anydrides, 2-quinolone types, and carboxylic acids) were determined using a differential infrared spectrometric technique combined with selective chemical reactions. The investigation involved two studies: in the first, a Wilmington (California) asphalt was separated into fractions of increasing polarity prior to air oxidation; the second was a 4-by-4 matrix in which four FHWA study asphalts were oxidized on four different aggregates. The latter study was designed to determine relative amounts of oxidation on aggregates and on inert surfaces. The first study showed that quartizite aggregate significantly catalyzed the oxidation of saturate and aromatic fractions. The polar aromatic and asphaltene fractions of this asphalt, contain components that also catalyze the oxidation of saturates and aromatics and probably the other fractions of the asphalt. Components in asphalt inhibited the catalytic effect of the quartizite surface on asphalt oxidation. The second study demonstrated the catalytic effect of aggregate surfaces on the oxidation of whole asphalts. The aggregate that had shown the least interaction with components in the asphalts appeared to exhibit the greatest catalytic effect on asphalt oxidation. Although aggregate surfaces appear to be potent catalyst for asphalt oxidation, the catalytic appears to be greatly reduced by components in the asphalt; it is believed that a large portion of the oxidation in asphalt-aggregate mixes results form catalysis by components naturally present in the asphalt.

  • Corporate Authors:

    University of Minnesota, Minneapolis

    155 Experimental Engineering Building
    Minneapolis, MN  USA  55455
  • Authors:
    • Petersen, J C
    • Barbaar, F A
    • Dorrence, S M
  • Conference:
  • Publication Date: 1974

Media Info

  • Features: References; Tables;
  • Pagination: p. 162-177
  • Serial:
    • Volume: 43

Subject/Index Terms

Filing Info

  • Accession Number: 00125401
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Oct 18 1975 12:00AM