# US 2012/0083613 A1 · Alumina support for silver catalyst, preparation and use thereof

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2012/0083613 A1
- Document ID: US20120083613A1
- Status: Published application
- Kind: A1
- Application number: 13/251,140
- Filed: 2011-09-30
- Published: 2012-04-05
- Earliest claimed: 2010-09-30
- Assignees: Beijing Research Institute of Chemical Industry, China Petroleum & Chemical Corporation; China Petroleum & Chemical Corporation
- Inventors: Wei LIN; Jinbing Li; Jianshe Chen; Zhixiang Zhang; Qiang Lin; Jun Jiang; Shuyuan Cao; Qian Xue; Shujuan Wang; Zhiqiang Tang
- Web page: https://patentgrep.com/patent/US20120083613A1

## CPC

- C07D 301/03: by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds
- B01J 21/04: Alumina
- B01J 23/02: of the alkali- or alkaline earth metals or beryllium
- B01J 23/04: Alkali metals
- B01J 23/50: Silver
- B01J 23/66: Silver or gold
- B01J 23/688: {with manganese, technetium or rhenium}
- B01J 35/612: {less than 10 m2/g}
- B01J 35/633: {less than 0.5 ml/g}
- B01J 35/635: {0.5-1.0 ml/g}
- B01J 37/0009: {Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst}
- B01J 37/14: with gases containing free oxygen
- Y02P 20/52: using catalysts, e.g. selective catalysts
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)
- B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

The present invention relates to an alumina support for silver catalyst, a process for preparing said alumina support, a silver catalyst made from said alumina support, and a use of said silver catalyst in the production of ethylene oxide by the oxidization of ethylene. According to the present invention, the silver catalyst made from the support prepared by potassium melt technology can have a high selectivity.

## Claims

### Claim at position 1

1-13. (canceled)

### Claim 14

An alpha-alumina support, which is characterized by a specific surface area of 0.2-2.0 m2/g; a water absorption of not lower than 30%; a pore volume of 0.30-0.85 ml/g; and a potassium compound content, based on the weight of support and calculated as potassium element, of 0.001-2.0%.

### Claim 15

A process for preparing an alpha-alumina support, comprising the following steps:
I) preparing a mixture of:
component (a) of a trihydrate alpha-alumina at 5-90% by weight, based on the total weight of solids in the mixture;
component (b) of a pseudo-boehmite at 5-90% by weight, based on the total weight of solids in the mixture;
component (c) of a fluoride mineralizing agent at 0.01-3.0% by weight, based on the total weight of solids in the mixture;
component (d) of a potassium compound at 0.01-3.0% by weight, based on the total weight of solids in the mixture;
component (e) of a heavy alkaline-earth metal compound at 0-2.0% by weight, based on the total weight of solids in the mixture;
component (f) of a binder that is different from components (c) to (e) at 10-45% by weight, based on the total weight of components (a) to (e); and
component (g) an appropriate amount of water;
wherein the total weight of the solids in the mixture means the total weight of components (a) through (e); and wherein the total amount of all solid components in the mixture is 100% by weight;
II) kneading the mixture of step (I) homogenously and extruding into shape to give shaped bodies;
III) drying at least one of the shaped bodies from step (II), and then calcining it to form an alpha-alumina support; and
IV) optionally, water-washing the alpha-alumina support of step (III).

### Claim 16 (depends on 15)

The process of claim 15, wherein the mixture comprises potassium fluoride that is regarded as both components (c) and (d).

### Claim 17 (depends on 15)

The process of claim 15, wherein the mixture comprises a heavy alkaline-earth metal fluoride that is regarded as both components (c) and (e).

### Claim 18 (depends on 15)

The process of claim 15, wherein component (c) of the mixture formed in step (I) is selected from the group consisting of an inorganic fluoride, hydrogen fluoride, aluminum fluoride, ammonium fluoride, magnesium fluoride, cryolite, and combinations thereof.

### Claim 19 (depends on 15)

The process of claim 15, wherein the potassium compound of component (d) of the mixture formed in step (I) as is selected from the group consisting of an inorganic acid salt of potassium, an organic acid salt of potassium, potassium hydroxide, potassium nitrate, potassium fluoride, potassium nitrite, potassium carbonate, and combinations thereof.

### Claim 20 (depends on 15)

The process of claim 15, wherein the heavy alkaline-earth metal compound as component (e) of the mixture formed in step (I) is selected from the group consisting of strontium oxide, strontium sulfate, strontium acetate, strontium nitrate, strontium carbonate, strontium oxalate, barium oxide, barium sulfate, barium acetate, barium nitrate, barium carbonate, barium oxalate, and combinations thereof.

### Claim 21 (depends on 15)

The process of claim 15, wherein the binder as component (f) in the mixture formed in step (I) is an acid.

### Claim 22 (depends on 21)

The process of claim 21, wherein the acid is an aqueous nitric acid solution, wherein a volume ratio of nitric acid to water is selected from the group consisting of 1:1.25-1:10 and 1:2-1:4.

### Claim 23 (depends on 15)

The process of claim 15, wherein component (a) is at 15-85% by weight, component (b) is at 10-80% by weight, component (c) is at 0.1-2.5% by weight, component (d) is at 0.1-2.5% by weight, component (e) is at 0-1.0% by weight, and component (f) is at 10-35% by weight, based on the total weight of components (a) to (e).

### Claim 24 (depends on 15)

The process of claim 15, wherein component (a) is at 35-82% by weight, component (b) is at 15-62% by weight, component (c) is at 1.2-2.0% by weight, component (d) is at 0.3-1.2% by weight, component (e) is at 0-0.5% by weight, and component (f) is at 10-25% by weight, based on the total weight of components (a) to (e).

### Claim 25 (depends on 15)

The process of claim 15, wherein component (a) is at 65-82% by weight, component (b) is at 15-32% by weight, component (c) is at 1.2-2.0% by weight, component (d) is at 0.4-1.0% by weight, component (e) is at 0-0.5% by weight, and component (f) is at 10-25% by weight, based on the total weight of components (a) to (e).

### Claim 26 (depends on 15)

The process of claim 15, wherein component (a) is at 66.5-82% by weight, component (b) is at 15-30% by weight, component (c) is at 1.2-2.0% by weight, component (d) is at 0.4-1.0% by weight, component (e) is at 0-0.5% by weight, and component (f) is at 10-25% by weight, based on the total weight of components (a) to (e).

### Claim 27 (depends on 15)

The process of claim 15, wherein component (a) is at 66.5-82% by weight, component (b) is at 15-30% by weight, component (c) is at 1.2-2.0% by weight, component (d) is at 0.4-1.0% by weight, component (e) is at 0.2-0.5% by weight, and component (f) is at 10-25% by weight, based on the total weight of components (a) to (e).

### Claim 28 (depends on 1)

A silver catalyst for producing ethylene oxide by oxidation of ethylene, comprising:
an alpha-alumina support of claim 1, silver deposited on the alpha-alumina support, an optional alkali metal promoter, an optional alkaline-earth metal promoter, an optional rhenium promoter and optionally its co-promoter,
wherein silver is present in the silver catalyst in an amount selected from the group consisting of 1-40% and 5-25%, calculated based on silver atom and the total weight of the silver catalyst,
wherein the optional alkali metal promoter is present in the silver catalyst in an amount selected from the group consisting of 0-2000 ppm, 5-2000 ppm, and 5-1500 ppm, calculated based on alkali metal atom and the total weight of the silver catalyst,
wherein the optional rhenium promoter is present in the silver catalyst in an amount selected from the group consisting of 0-2000 ppm, 10-2000 ppm, and 100-1000 ppm, calculated based on rhenium atom and the total weight of the silver catalyst,
wherein the optional alkaline-earth metal promoter is present in the silver catalyst in an amount selected from the group consisting of 0-10000 ppm and 0-8000 ppm, calculated based on alkaline-earth metal atom and the total weight of the silver catalyst.

### Claim 29 (depends on 28)

The silver catalyst of claim 28, which is prepared by the method comprising the following steps:
(1) impregnating the alpha-alumina support with a solution containing sufficient amounts of a silver compound, an organic amine, an optional alkali metal promoter, an optional alkaline-earth metal promoter, and an optional rhenium promoter and optionally its co-promoter;
(2) filtering the impregnation solution; and
(3) activating the support obtained from step (2) in an oxygen-containing gas to produce the silver catalyst.

### Claim 30 (depends on 28)

The silver catalyst of claim 28, wherein:
the silver compound is selected from the group consisting of silver oxide, silver nitrate, silver oxalate, and combinations thereof;
the alkali metal promoter is selected from the group consisting of a lithium compound, a sodium compound, a potassium compound, a rubidium compound, a cesium compound, cesium nitrate, lithium nitrate, potassium hydroxide, and combinations thereof;
the rhenium promoter is selected from the group consisting of rhenium oxide, perrhenic acid, cesium perrhenate, ammonium perrhenate, and combinations thereof; and
the alkaline-earth metal promoter is selected from the group consisting of a magnesium compound, a calcium compound, a strontium compound, a barium compound, barium oxide, barium oxalate, barium sulfate, barium acetate, barium nitrate, strontium oxide, strontium oxalate, strontium sulfate, strontium acetate, strontium nitrate, magnesium oxide, magnesium oxalate, magnesium sulfate, magnesium acetate, magnesium nitrate, calcium oxide, calcium oxalate, calcium sulfate, calcium acetate, calcium nitrate, calcium oxide, calcium oxalate, calcium sulfate, calcium acetate, calcium nitrate, and combinations thereof.

### Claim 31 (depends on 29)

The silver catalyst of claim 29, wherein the activating step (3) is conducted in air or a nitrogen-oxygen mixed gas with an oxygen content of 21 vol % or less.

### Claim 32 (depends on 29)

The silver catalyst of claim 29, wherein in the activating step (3) is conducted at a temperature selected from the group consisting of 180-700° C. and 200-500° C. and for a time period selected from the group consisting of 1-120 mins and 2-60 mins.

### Claim 33 (depends on 28)

A method of producing ethylene oxide by the oxidation of ethylene using the silver catalyst of claim 28.