Enhanced propylene production in OTO process with modified zeolites

Patent metadata

Field	Value
Publication number	US-9643897-B2
Application number	US-201514636718-A
Country	US
Kind code	B2
Filing date	Mar 3, 2015
Priority date	Mar 3, 2015
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A process for oxygenate conversion using a family of crystalline aluminosilicate zeolites that is a layered pentasil zeolite with a silica or fluorine modified surface. These zeolites are represented by the empirical formula:

M m n+ R r p+ Al 1-x E x Si y O z

where M is an alkali, alkaline earth, or rare earth metal such as sodium or potassium, R can be a mixture of organoammonium cations and E is a framework element such as gallium, iron, boron, or indium. These zeolites are characterized by unique x-ray diffraction patterns and compositions and have catalytic properties for carrying out oxygenate conversion processes.

First claim

What is claimed is:

1. A process for the conversion of oxygenates to olefins comprising:
passing an oxygenate feedstream to an oxygenate conversion reactor operated at oxygenate conversion reaction conditions, wherein the reactor includes a catalyst having a layered pentasil structure and wherein the surface of the catalyst has been modified with silica or fluorine, to generate a process stream comprising olefins, wherein the catalyst is a zeolite having a microporous crystalline structure comprising a framework of AlO 2 and SiO 2 tetrahedral units, and an empirical composition in the as synthesized and anhydrous basis expressed by the empirical formula of:
M m n+ R r p+ AlSi y O z

where M is at least one exchangeable cation selected from the group consisting of alkali and alkaline earth metals, “m” is the mole ratio of M to Al and varies from 0 to 3, R is at least one organoammonium cation selected from the group consisting of quaternary ammonium cations, diquaternary ammonium cations, quaternary phosphonium cations, methonium cations, and mixtures thereof, “r” is the mole ratio of R to Al and has a value of about 0.1 to about 30, “n” is the weight average valence of M and has a value of about 1 to about 2, “p” is the weighted average valence of R and has a value of about 1 to about 2, “y” is the mole ratio of Si to Al and varies from greater than 32 to about 200 and “z” is the mole ratio of O to Al and has a value determined by the equation:
z= ( m·n+r·p+ 3+4· y )/2:and

wherein the zeolite is further characterized in that it has the x-ray diffraction pattern having at least the d spacing and intensities set forth in the following Table A:

TABLE A

2Θ
d(Å)
I/Io

7.92-7.99
11.04-11.31
m

8.79-8.88
 9.94-11.09
m

20.28-20.56
4.31-4.35
w

23.10-23.18
3.83-3.84
vs

23.86-24.05
3.69-3.72
m

29.90-30.05
2.97-2.98
w

45.02-45.17
2.00-2.01
 w.

2. The process of claim 1 wherein the zeolite has a mesopore surface area between 140 m 2 /g and 400 m 2 /g.

3. The process of claim 1 wherein the zeolite further comprises a microporous crystalline structure comprising a framework of AlO 2 and SiO 2 tetrahedral units, further including the element E and having the empirical composition in the as synthesized and anhydrous basis expressed by the empirical formula of:
M m n+ R r p+ Al 1-x E x Si y O z

where “m” is the mole ratio of M to (Al+E) and varies from 0 to 3, “r” is the mole ratio of R to (Al+E) and has a value of about 0.1 to about 30, E is an element selected from the group consisting of gallium, iron, boron, indium and mixtures thereof, “x” is the mole fraction of E and has a value from 0 to 1.0, “y” is the mole ratio of Si to (Al+E) and varies from greater than 32 to about 200 and “z” is the mole ratio of O to (Al+E) and has a value determined by the equation:
z=( m·n+r·p+ 3 +4· y )/2.

4. The process of claim 1 further comprising separating the process stream into an ethylene stream, a propylene stream, a C 4 stream, a C 5 stream, and a C 5+ heavies stream, or some combination thereof.

5. The process of claim 4 further comprising passing the heavies stream, comprising C 4+ olefins, to an olefin cracking unit, or passing the C 4 stream and/or the C 4 + stream to a metathesis unit along with some portion or all of the ethylene stream.

6. The process of claim 1 wherein the oxygenates comprise alcohols, aldehydes, ethers and mixtures thereof.

7. The process of claim 6 wherein the oxygenate comprises methanol.

8. The process of claim 1 wherein oxygenate conversion reactor comprises a fluidized reactor bed, and wherein the oxygenate conversion reactor generate an effluent stream comprising catalyst and a process fluid, wherein the effluent stream is separated into a spent catalyst stream and the process stream comprising olefins.

9. The process of claim 8 wherein the catalyst stream is passed to a regenerator to generate a regenerated catalyst stream.

10. The process of claim 9 further comprising passing the regenerated catalyst stream to a stripper, to generate a stripped catalyst stream comprising catalyst with carbon oxides removed.

11. The process of claim 10 further comprising passing the stripped catalyst stream to the oxygenate conversion reactor.

12. The process of claim 1 wherein the oxygenate conversion reaction conditions include a temperature in the range from 300° C. to 600° C.

13. The process of claim 1 wherein the oxygenate conversion reaction conditions include an oxygenate partial pressure in the range from 100 kPa to 800 kPa.

14. A process for the conversion of oxygenates to olefins comprising:
passing an oxygenate feedstream to an oxygenate conversion reactor operated at oxygenate conversion reaction conditions, wherein the reactor includes a catalyst having a 2-D layered pentasil structure and wherein the surface of the catalyst has been modified with silica or fluorine, to generate a process stream comprising olefins, wherein the catalyst is a zeolite having a microporous crystalline structure comprising a framework of AlO 2 and SiO 2 tetrahedral units, and having the empirical composition in the as synthesized and anhydrous basis expressed by the empirical formula of:
M m n+ R r p+ Al 1-x E x Si y O z ;

wherein M is at least one exchangeable cation selected from the group consisting of alkali and alkaline earth metals, m″ is the mole ratio of M to (Al+E) and varies from 0 to 1, R is at least one organoammonium cation selected from the group consisting of quaternary ammonium cations, diquaternary ammonium cations, quaternary phosphonium cations, methonium cations, and mixtures thereof, “r” is the mole ratio of R to (Al+E) and has a value of 0.1 to about 30, “n” is the weight average valence of M and has a value of 1 to 2, “p” is the weighted average valence of R and has a value of 1 to 2, E is an element selected from the group consisting of gallium, iron, boron, indium and mixtures thereof, “x” is the mole fraction of E and has a value from 0 to 1.0, “y” is the mole ratio of Si to (Al+E) and varies from greater than 32 to about 200 and “z” is the mole ratio of O to (Al+E) and has a value determined by the equation:
z= ( m·n+r·p+ 3 +4· y )/2

and it is characterized in that it has the x-ray diffraction pattern having at least the d spacing and intensities set forth in the following Table A:

Assignees

• Uop Llc

Inventors

• Jan Deng-Yang
• Schoenfeldt Nicholas J
• Moscoso Jaime G

Classifications

• B01J35/45

  Nanoparticles · CPC title

• B01J35/70

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

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/77

  Compounds characterised by their crystallite size · CPC title

• C07C2529/40

  of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11 · CPC title