Prepn process of hyperastable Y-type RE molecular sieve

Abstract

The invention relates to a method for preparing a novel rare earth ultra-stable Y molecular sieve containing vanadium-resistant components used for catalytic cracking of heavy oil. The NaY type molecular sieve is used as a raw material, and the chemical dealumination complexing agent contains oxalic acid or oxalate and its At the same time, rare earth ions are introduced into the mixture in the later stage of the chemical dealumination reaction to form rare earth precipitates, and then through hydrothermal treatment, the purpose of ultra-stabilization and the introduction of rare earth ions and independent phase oxidation of rare earth can be achieved. The precipitated rare earth precursors formed include rare earth oxalate. Compared with conventional REY, REHY or REUSY, the molecular sieve has simple preparation process, high utilization rate of rare earth, and has the characteristics of uniform aluminum distribution, developed secondary pores, good hydrothermal stability, high activity, and strong anti-vanadium pollution ability. It is suitable for Used in the preparation of heavy oil catalytic cracking catalyst.

Description

technical field [0001] The invention relates to a method for preparing hydrocarbon cracking molecular sieves. To be precise, it is a preparation method of rare earth ultra-stable Y-type molecular sieve suitable for heavy oil cracking, especially heavy oil cracking with high vanadium content. Background technique [0002] Looking at the changes in catalytic cracking feedstock oil at home and abroad, the feedstock for catalytic cracking has changed from traditional vacuum wide distillate oil to residual oil or residual oil, because residual oil contains more heavy metals (nickel, vanadium, etc.), Colloids and asphaltenes make cracking catalysts face problems such as how to improve coke selectivity and anti-heavy metal pollution performance. [0003] In the cracking reaction, due to the deposition of metals such as nickel and vanadium on the catalyst, the activity of the catalyst is reduced. Therefore, it is necessary to continuously unload and replenish new catalyst from the ...

AI Technical Summary

Problems solved by technology

Chinese patents CN 86107531A and CN86107598A reported a similar rare earth introduction method, that is, RE(OH) 3 Introducing rare earths to the precursors; the dealuminated complexing agents used in Chinese patents CN 1042523A and CN 1031500C include: oxalic acid, ammonium oxalate, ethylenediaminetetraacetic acid and edetate, but do not involve the formation of rare earth oxalate precipitates