Research On The Property And Cracking Ability Of Modified REY Zeolite

In order to increase the activity and hydrothermal stability of REY zeolite and decrease the production cost, a modified REY zeolite(HAY) was developed. During the producing process, HAY zeolite was made by depositing some SiO₂, exchanging rare earth element and injecting superheating stream while calcining. The FCC catalyst which took HAY zeolite as active component got a good result in the heavy oil cracking test.The preparation condition and property of HAY zeolite were investigated. The results showed that the treatment of hydrothermal calcinations controlled the formation of large molecule "(RE-O-RE)⁴⁺"and caused the migration of more RE³⁺ from super cage to sodalite cage , which made useful effect on improving the activity and stability of zeolite. The active SiO₂ which was deposited on zeolite could increase the crystallinity of HAY zeolite and adjust the acidity to extent.This article also studied the reacting proverties of HAY zeolite catalyst. The evaluation results showed that compared with conventional REY zeolite catalyst, HAY zeolite catalyst had excellent performances in high activity, good activity stability and good carbon tolerance. The evaluation of fixed fluidizing bed test showed that using improved HAY zeolite catalyst, the product yield distribution with higher gasoline and diesel yield, lower slurry yield was achieved and the conversion was also some increased.The producing process of HAY zeolite catalyst was simplied and one exchanging procedure and one calcining procedure was cut down compared with conventional REY zeolite production thus preparation cost was reduced in large extent.