Two-stage hydrocarbon cracking - with catalysts contg. ZSM-5 zeolite in rising stream reactors

摘要

Hydrocarbon feedstocks (esp. gas oils) are cracked in a 2-stage process using 2 rising-stream reactors, in which the 1st reactor contains a catalyst contg. 2 cracking components, one of which is a zeolite with the compsn. 0.9 plus-or-minus 0.2 M2/nO: M1zO3:5-100 ZO2: chi H2O(where M is an n-valent cation; M1 is Al or Ga; Z is Si or Ge; chi = 0-40), and the 2nd reactor, operating with a recirculated feedstock (esp. the unreacted naphtha fraction from the 1st stage), contains a catalyst with 2 cracking components, one of which is a zeolite as defined above. The other component of the catalysts is pref. a base-exchanged synthetic fau asite (esp. Y or X type).