The effect of naphthenic components in the visbreaking modeling

The present work deals with a mechanistic model of visbreaking (VB) process. It allows satisfactory predictions of feed and products, amounts and properties overcoming the typical limitations of the empirical models (for instance, in terms of flexibility, extrapolability and so on). The mechanistic VB modeling was initially performed by taking into account just two macro-classes of pseudo-components, paraffins and aromatics [Dente, M., Bozzano, G., & Rossi, M. (1993). Reactor modelling of the visbreaking process. In Proceedings of the first conference on chemical and process engineering, Florence (p. 163); Dente, M., Bozzano, G., & Bussani, G., (1997). A comprehensive program for visbreaking simulation: Products amount and their properties prediction. Computers and Chemical Engineering, 21, 1125; Bozzano, G., Dente, M., Sugaya, M., & McGreavy C., (1998). The characterization of residual hydrocarbon fractions with model compounds retaining the essential information, preprints of Symposia, Vol. 43, No. 3, 216th ACS National Meeting-Boston, (p. 653)]. More recently, new experimental data related to the visbreaking of highly naphthenic residues have induced to extend the model by including naphthenic components (and their primary products, like cyclo-olefines). The importance of this extension in VB modeling is here described and underlined. Particularly it is discussed the effect of naphthenes presence on VB residue stability, against asphaltenes flocculation.