Layered catalyst loading for synthesis gas conversion

Patent metadata

Field	Value
Publication number	US-2020231525-A1
Application number	US-202016738624-A
Country	US
Kind code	A1
Filing date	Jan 9, 2020
Priority date	Jan 18, 2019
Publication date	Jul 23, 2020
Grant date	—

Abstract

Systems and methods are provided for conversion of gas phase reactants including CO and H 2 to C 2+ products using multiple catalysts in a single reactor while reducing or minimizing deactivation of the catalysts. Separate catalysts can be used that correspond to a first catalyst, such as a catalyst for synthesis of methanol from synthesis gas, and a second catalyst, such as a catalyst for conversion of methanol to a desired C 2+ product. The separate catalysts can be loaded into the reactor in distinct layers that are separated by spacer layers. The spacer layers can correspond to relatively inert particles, such as silica particles. Optionally, the spacer layer can include an adsorbent, such as boron supported on alumina or boron carbide particles. The adsorbent can be suitable for selective adsorption of the one or more reaction products (such as one or more reaction by-products), to allow for further reduction or minimization of the deactivation of the conversion catalysts.

First claim

1 . A method for converting synthesis gas to C 2+ products, comprising:
exposing a feed comprising CO and H 2 to a plurality of layered catalyst groupings under conversion conditions to form a conversion effluent comprising C 2+ products, each layered catalyst grouping comprising
a) a methanol synthesis catalyst layer comprising methanol synthesis catalyst particles;
b) a second spacer layer comprising second layer spacer particles;
c) an acidic catalyst layer comprising acidic catalyst particles; and
d) a fourth spacer layer comprising fourth layer spacer particles,
wherein a combined weight of the methanol synthesis catalyst particles in the methanol synthesis catalyst layers comprises a first weight, a combined weight of the second layer spacer particles in the second spacer layers comprising 10% to 110% of the first weight, and wherein a combined weight of the acidic catalyst particles in the acidic catalyst particle layers comprises a third weight, a combined weight of the fourth layer spacer particles in the fourth spacer layers comprising 10% to 110% of the first weight.

2 . The method of claim 1 , wherein the feed is exposed to the plurality of layered catalyst groupings without intermediate separation.

3 . The method of claim 1 , wherein the plurality of layered catalyst groupings comprises 3 or more layered catalyst groupings, or wherein the plurality of layered catalyst groupings comprises 10 or less layered catalyst groupings, or a combination thereof.

4 . The method of claim 1 , wherein the acidic catalyst particles comprise an Alpha value of 1.0 or more.

5 . The method of claim 1 , wherein the acidic catalyst particles comprise alumina, silica alumina, a mixed metal oxide, a zeolite, or a combination thereof.

6 . The method of claim 1 , wherein the conversion conditions comprise a temperature of 200° C. to 300° C. and a pressure of 2.0 MPa-g to 5.0 MPa-g, the C 2− products comprising dimethyl ether.

7 . The method of claim 1 , wherein the conversion conditions comprise a temperature of 250° C. to 350° C. and a pressure of 2.0 MPa-g to 5.0 MPa-g, the C 2− products comprising C 2+ olefins.

8 . The method of claim 1 , wherein the conversion conditions comprise a temperature of 300° C. to 450° C. and a pressure of 2.0 MPa-g to 5.0 MPa-g, the C 2− products comprising aromatic hydrocarbons.

9 . The method of claim 1 , wherein 30 mol % or more of the CO in the feed is converted during the exposing to the plurality of layered catalyst groupings.

10 . The method of claim 1 , wherein at least one of the second layer spacer particles and the fourth layer spacer particles comprise particles having an Alpha value of less than 1.0.

11 . The method of claim 1 , wherein the second layer spacer particles are substantially the same as the fourth layer spacer particles.

12 . The method of claim 1 , wherein exposing the feed to a methanol synthesis catalyst layer further comprises forming a first intermediate effluent, the first intermediate effluent comprising an equilibrium amount of methanol based on the conversion conditions.

13 . The method of claim 1 , wherein exposing the feed to an acidic catalyst layer further comprises forming a third intermediate effluent, the third intermediate effluent comprising an equilibrium amount of at least one methanol conversion product based on the conversion conditions.

14 . The method of claim 1 , wherein exposing the feed to a second spacer layer comprises:
generating a first intermediate effluent from a methanol synthesis catalyst layer, the first intermediate effluent comprising a plurality of reaction products; and exposing the first intermediate effluent to the second spacer layer to form a second intermediate effluent, a concentration of at least one reaction product of the plurality of reaction products in the second intermediate effluent being reduced by 10 wt % or more relative to a weight of the at least one reaction product in the first intermediate effluent.

15 . The method of claim 1 , wherein exposing the feed to a fourth spacer layer comprises:
generating a third intermediate effluent from an acidic catalyst layer, the third intermediate effluent comprising a third plurality of reaction products; and exposing the third intermediate effluent to the fourth spacer layer to form a fourth intermediate effluent, a concentration of at least one reaction product of the third plurality of reaction products in the fourth intermediate effluent being reduced by 10 wt % or more relative to a weight of the at least one reaction product in the third intermediate effluent.

16 . The method of claim 1 , wherein at least one of the second layer spacer particles and the fourth layer spacer particles comprise adsorbent particles.

17 . The method of claim 1 , wherein the adsorbent particles comprise supported boron oxide particles, boron carbide particles, or a combination thereof.

18 . The method of claim 17 , wherein 35 mol % or more of the CO in the feed is converted during the exposing to the layered catalyst groupings.

19 . The method of claim 1 , wherein the methanol synthesis catalyst layers comprise different weights of methanol synthesis catalyst particles, or wherein the acidic catalyst layers comprise different weights of acidic catalyst particles, or a combination thereof.

20 . The method of claim 1 , wherein a weight hourly space velocity of the feed relative to a methanol synthesis catalyst layer is 2.0 hr −1 or more, or 5.0 hr −1 or more; or wherein a weight hourly space velocity of the feed relative to an acidic catalyst layer is 2.0 hr −1 or more, or 5.0 hr −1 or more; or a combination thereof.

21 . A method for converting gas phase reactants in multiple steps, comprising:
exposing a feed comprising CO and H 2 to a plurality of layered catalyst groupings under conversion conditions to form a conversion effluent comprising C 2+ products, the exposing of the feed to a layered catalyst grouping comprising:
a) exposing the feed to a first catalyst layer comprising first catalyst particles under the conversion conditions to form a first intermediate effluent comprising a first plurality of reaction products;
b) exposing the first intermediate effluent to a second spacer layer comprising second layer spacer particles under the conversion conditions to form a second intermediate effluent, a concentration of at least one reaction product of the plurality of reaction products in the second intermediate effluent being reduced by 10 wt % or more relative to a weight of the at least one reaction product in the first intermediate effluent;
c) exposing the second intermediate effluent to a third catalyst layer comprising third catalyst particles under the conversion conditions to form a third intermediate effluent comprising a third plurality of reaction products, the conversion conditions being effective for conversion of one or more reaction products from the first plurality of reaction products to form the third plurality of reaction products; and
d) exposing the third intermediate effluent to a fourth spacer layer comprising fourth layer spacer particles, a concentration of at least one reaction product of the third plurality of reaction products in the fourth intermediate effluent being reduced by 10 wt % or more relative to a weight of the at least one reaction product in the third intermediate effluent
wherein a combined weight of the first catalyst particles in the first catalyst layers comprises a first weigh

Assignees

• Exxonmobil Res & Eng Co

Inventors

• Dakka Jihad M
• Sikorsky Michael J
• Ramkrishnan Aruna
• Bai Chuansheng
• Lee Anita S
• Kamakoti Preeti
• Kovvali Anjaneya S
• Walp Jenna L

Classifications

• C07C41/01 Primary

  Preparation of ethers · CPC title

• B01J2208/025

  Two or more types of catalyst · CPC title

• C07C31/04

  Methanol · CPC title

• B01J8/02

  with stationary particles, e.g. in fixed beds · CPC title

• C07C41/09 Primary

  by dehydration of compounds containing hydroxy groups · CPC title