Heavy oil catalytic cracking catalyst and preparation method therefor

Patent metadata

Field	Value
Publication number	US-9844772-B2
Application number	US-201214364536-A
Country	US
Kind code	B2
Filing date	Apr 13, 2012
Priority date	Dec 15, 2011
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

The present invention relates to a heavy oil catalytic cracking catalyst and preparation method thereof. The catalyst comprises 2 to 50% by weight of an ultra-stable rare earth type Y molecular sieve, 0.5 to 30% by weight of one or more other molecular sieves, 0.5 to 70% by weight of clay, 1.0 to 65% by weight of high-temperature-resistant inorganic oxides, and 0.01 to 12.5% by weight of rare earth oxide. The ultra-stable rare earth type Y molecular sieve is obtained as follows: the raw material, NaY molecular sieve, is subjected to a rare earth exchange and a dispersing pre-exchange, and the molecular sieve slurry is filtered, washed and subjected to a first calcination to produce a “one-exchange one-calcination” rare earth sodium Y molecular sieve, wherein the order of the rare earth exchange and the dispersing pre-exchange is not limited; and the “one-exchange one-calcination” rare earth sodium Y molecular sieve is further subjected to ammonium salt exchange for sodium reduction and a second calcination. The catalyst provided in the present invention is characteristic in its high heavy-oil-conversion capacity, a high total liquid yield and a high light oil yield.

First claim

What is claimed is:

1. A heavy oil catalytic cracking catalyst, characterized in that the catalyst comprises 2% to 50% by weight of an ultra-stable rare earth type Y molecular sieve, 0.5% to 30% by weight of one or more other molecular sieves, 0.5% to 70% by weight of clay, 1.0% to 65% by weight of high-temperature resistant inorganic oxides, and 0.01% to 12.5% by weight of rare earth oxide;
wherein the ultra-stable rare earth type Y molecular sieve is an ultra-stable rare earth type Y molecular sieve having 0.5% to 25% by weight of rare earth oxide, not more than 1.2% by weight of sodium oxide, a crystallinity of 40% to 75%, and a lattice parameter of 2.449 nm to 2.472 nm; and
wherein the ultra-stable rare earth type Y molecular sieve is prepared from a NaY molecular sieve as a raw material by a preparation method in which a molecular sieve slurry of the raw material is subjected to a rare earth exchange and a dispersing pre-exchange, then the molecular sieve slurry is further filtered, washed, and subjected to a first calcination to produce an intermediate rare earth sodium Y molecular sieve, wherein the order of the rare earth exchange and the dispersing pre-exchange steps is not limited,
the rare earth exchange and the dispersing pre-exchange being consecutively conducted without a calcination process therebetween, and the intermediate rare earth sodium Y molecular sieve then being subjected to an ammonium salt exchange for sodium reduction and a second calcination so as to obtain an ultra-stable rare earth type Y molecular sieve;
wherein the dispersing pre-exchange refers to a process of adjusting the molecular sieve slurry's concentration to a solid content of 80 to 400 g/L and adding 0.2% to 7% by weight of a dispersing agent to carry out dispersing pre-exchange at an exchange temperature of 0° C. to 100° C. for 0.1 to 1.5 h;
wherein the dispersing agent in the dispersing pre-exchange process is selected from one or more of sesbania gum powder, boric acid, urea, ethanol, polyacrylamide, acetic acid, oxalic acid, adipic acid, formic acid, hydrochloric acid, nitric acid, citric acid, salicylic acid, tartaric acid, benzoic acid, and starch; and
wherein no ammonium salt is used in the rare earth exchange or the dispersing pre-exchange.

2. The catalyst according to claim 1 , characterized in that the other molecular sieves are selected from one or more of type Y zeolite, L zeolite, ZSM-5 zeolite, β zeolite, aluminum phosphate zeolite, or Ω zeolite.

3. The catalyst according to claim 1 , characterized in that the other molecular sieves are one or more of HY, USY, REY, REHY, REUSY, H-ZSM-5, and β zeolite.

4. The catalyst according to claim 1 , characterized in that the clay is selected from one or more of kaolin, halloysite, montmorillonite, sepiolite, and perlite.

5. The catalyst according to claim 1 , characterized in that the high-temperature-resistant inorganic oxide is selected from one or more of Al 2 O 3 , SiO 2 , SiO 2 —Al 2 O 3 , and AlPO 4 .

6. The catalyst according to claim 1 , characterized in that the preparation process further comprises:
preparation of the heavy oil catalyst, wherein the ultra-stable rare earth type Y molecular sieve, one or more other molecular sieves, clay, and a precursor of a high-temperature resistant inorganic oxide are mixed, homogenized, shaped by spraying, calcinated and washed, to obtain the heavy oil catalyst product.

7. The catalyst according to claim 1 , characterized in that during the rare earth exchange, the mass ratio RE 2 O 3 /Y zeolite is 0.005 to 0.25, the exchange temperature is 0° C. to 100° C., the exchange pH is 2.5 to 6.0, and the exchange time is 0.1 to 2 h.

8. The catalyst according to claim 1 , characterized in that during the rare earth exchange, the mass ratio RE 2 O 3 /Y zeolite is 0.01 to 0.20, the exchange temperature is 60° C. to 95° C., exchange pH is 3.5 to 5.5, and the exchange time is 0.3 to 1.5 h; and
during the dispersing pre-exchange, the amount of the dispersing agent added is 0.2% to 5% by weight, the exchange temperature is 60° C. to 95° C., and the exchange time is 0.1 to 1.5 h.

9. The catalyst according to claim 1 , characterized in that, between the rare earth exchange and the dispersing pre-exchange, the molecular sieve slurry is washed and filtered.

10. The catalyst according to claim 1 , characterized in that tank-type exchange, belt-type exchange and/or filter cake exchange is employed for the exchange process of the rare earth exchange or the dispersing pre-exchange.

11. The catalyst according to claim 1 , characterized in that, in the process of the rare earth exchange, a rare earth compound solution is divided into multiple portions for multiple exchanges, and each of the multiple exchanges is a tank-type exchange, a belt-type exchange and/or a filter cake exchange.

12. The catalyst according to claim 1 , characterized in that, in the process of the dispersing pre-exchange, the dispersing agent is divided into multiple portions for multiple exchanges, and each of the multiple exchanges is a tank-type exchange, a belt-type exchange and/or a filter cake exchange.

13. The catalyst according to claim 1 , characterized in that the rare earth exchange and the dispersing pre-exchange are carried out alternately multiple times.

14. The catalyst according to claim 1 , characterized in that the calcination condition for the first calcination of the molecular sieve is calcination at 350° C. to 700° C. under 0 to 100% water vapor for 0.3 to 3.5 h.

15. The catalyst according to claim 6 , characterized in that the precursor of the high-temperature-resistant inorganic oxide is selected from the group consisting of silica-alumina gel, silica sol, alumina sol, silica-alumina composite sol, and pseudoboehmite.

16. The catalyst according to claim 11 , characterized in that the rare earth compound is rare earth chloride, rare earth nitrate or rare earth sulfate.

17. The catalyst according to claim 16 , wherein the rare earth in the rare earth compound is lanthanum-rich rare earth, cerium-rich rare earth, pure lanthanum or pure cerium.

18. The catalyst according to claim 1 , characterized in that the calcination condition for the second calcination is calcination at 200° C. to 700° C. for 0.05 to 4 hours.

19. The catalyst according to claim 6 , characterized in that the calcination condition is calcination at 300° C. to 650° C. for 0.1 to 3.5 hours.

20. The catalyst according to claim 6 , characterized in that the washing conditions are as follows: the weight ratio water/catalyst is 0.5 to 35, the washing temperature is 20° C. to 100° C., and the washing duration is 0.1 to 0.3 hours.

Assignees

• Gao Xionghou
• Zhang Haitao
• Tan Zhengguo
• Li Di
• Ji Dong
• Duan Hongchang
• Zhang Chenxi
• Petrochina Co Ltd

Inventors

• Gao Xionghou
• Zhang Haitao
• Tan Zhengguo
• Li Di
• Ji Dong
• Duan Hongchang
• Zhang Chenxi

Classifications

• B01J35/70

  characterised by their crystalline properties, e.g. semi-crystalline (catalysts comprising carbon B01J21/18; molecular sieves B01J29/00) · CPC title

• B01J35/51

  Spheres · CPC title

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• B01J35/109

  Operations & Transport · mapped topic

• B01J35/002

  Operations & Transport · mapped topic