Characteristic features of liquid-phase oxidation of vacuum tower bottoms in the presence of modifiers

Resumo

The influence of modifiers affecting the structural organization of a petroleum system and the kinetics of oxidation of vacuum distillation bottoms have been studied. It has been shown that the introduction of modifiers into the petroleum feedstock alters the ratio of the dispersed phase to the dispersion medium, thereby affecting the rate of the oxidation process. It has been found that the main factor determining the performance of modifiers affecting the structure of the petroleum system is the modifier nature. The maximum concentration of modifiers in the vacuum tower bottoms (VTB) was 5.0 wt %. The dependence of the oxidation rate upon the duration of oxidation has been determined for the modifiers. It has been shown that brown-coal pyrolysis tar introduced into VTB has an inhibitory effect, and oil shale pyrolysis tar and a diamond blend initiate the oxidation process. For blown asphalts produced from modified and unmodified VTB, expressions relating the softening point and penetration have been obtained. The properties of different blown asphalts obtained from the feedstock modified with the test additives at optimal concentrations have been compared.