Texturization molecular weight distributions

Another coke formed in a FCC unit is occluded or residual coke. In a commercial unit this coke corresponds to coke formed on catalyst porosity and its content depends on textural properties of the catalyst (pore volume and pore size distribution) and the stripping system capacity in the reaction section. Finally on the FCC catalyst rests some high-molecular weight of nonvaporized hydrocarbons. These molecules do not vaporize or react at the reactor conditions and accumulate in the catalyst pores like a soft carbonaceous residue with high hydrogen content. 

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