Selectivity of Cracking Reactions

Laxminarasimhan et al. treated the problem of maximizing the liquid yield in hydrocracking by introducing a distribution function p k, K) characterizing cracking stoichiometry 

The hydrocracking rate constant k is assumed to be a monotonic function of boiling point. And p k, x) describes the amount of species with reactivity k that is formed from the cracking of the species with reactivity K Its properties are (1) p k, x) = 0 for x (2) p k, 0 and has a finite, small value when 

Z)(s) accounts for the cracking of all species with reactivity K, since the mass balance is written in the k space. 

A skewed Gaussian-type distribution function can depict the yield distributions. The resulting model reproduces published pilot-plant and commercial data on vacuum gas oil hydrocracking.This has led to the development of a hydrocracking process model. Selective cracking in FCC has also been addressed.Browarzik and Kehlen used a fragmentation-based model for n-alkane hydrocracking. Similar approaches have been used for polymer reaction systems.  

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