Intensification of processes of hydrotreating and catalytic cracking of activated feedstock

Abstract

The maximum kinetic stability of a feedstock with an activating additive is obtained with optimal content of the additive; this can be found from the minimum on a plot of the low-temperature kinematic viscosity of the blend (at a temperature 2-5 ~ above the solid point of the feed) [I] or the surface tension of the blend [2] as a function of the concentration of additive. For a residual petroleum feedstock, the optimal additive concentration is determined on the basis of the so-called stability factor [3] or the xylene number [4]. Direct measurements of the mean effective dimensions of the disperse-phase particles by means of a photoelectric colorimeter or a spectrophotometer have confirmed the correspondence of the maximum kinetic stability of the feed plus activating additive to the minimum mean dimensions of the disperse-phase particles. A number of activating additives have been tested in the process of catalytic cracking a heavy petroleum resid; these additives can be divided into three groups: aromatic additives, oxygen-containing concentrate, and surface-active substances. In Table 1 we have listed the most typical additives.