# US 5,700,440 A · Selective oxidation of hydrogen sulfide in the presence of iron-based catalysts

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

- Number: US 5,700,440 A
- Document ID: US5700440A
- Status: Granted
- Kind: A
- Application number: 08/523,362
- Filed: 1995-09-05
- Granted: 1997-12-23
- Earliest claimed: 1995-09-05
- Assignees: National Science Council
- Inventors: Kuo-Tseng Li; Yen-Chun Ker
- Web page: https://patentgrep.com/patent/US5700440A

## CPC

- B01D 53/8612: {Hydrogen sulfide}
- B01D 2255/20738: Iron
- B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28)

## Abstract

The present invention discloses a method of selectively oxidizing hydrogen sulfide to elemental sulfur, in which a H.sub.2 S-containing gas mixture contacts with an oxygen-containing gas at 50.degree.-500.degree. C. in the presence of an iron-based catalyst. The reaction product mixture contains substantially no sulfur dioxide. The iron-based catalyst, in addition to iron atom, further contains a promoter of cerium, tin or antimony.

## Claims

### Claim 1

A process for recovering elemental sulfur from a gas mixture containing hydrogen sulfide consisting essentially of contacting said gas mixture with an oxygen-containing gas to result in a gas having a molar ratio of hydrogen sulfide to oxygen that is less than 2 in an temperature range of from about 50.degree. C. to about 400.degree. C. in the presence of a supported iron (III) oxide catalyst, and a promoter for the selective oxidation of hydrogen sulfide to elemental sulfur, said promoter is a cerium component, a tin component, or an antimony component.

### Claim 2 (depends on 1)

A process according to claim 1 wherein said promoter is a cerium component.

### Claim 3 (depends on 1)

A process according to claim 1 wherein said promoter is a tin component.

### Claim 4 (depends on 1)

A process according to claim 1 wherein said promoter is an antimony component.

### Claim 5 (depends on 1)

A process according to claim 1 wherein said iron-(III) oxide catalyst has a molar ratio of iron atom to said promoter ranging from 1:100 to 100:1.

### Claim 6 (depends on 5)

A process according to claim 5 wherein said iron-(III) oxide catalyst has a molar ratio of iron atom to said promoter ranging from 1:10 to 10:1.

### Claim 7 (depends on 1)

A process according to claim 1 wherein said temperature ranges from about 100.degree. C. to about 350.degree. C.

### Claim 8 (depends on 1)

A process according to claim 1 wherein said iron-(III) oxide catalyst is in the form of monolith, particle or pellet.

### Claim 9 (depends on 1)

A process according to claim 1 wherein said iron-(III) oxide catalyst is supported on a porous carrier selected from the group consisting of alumina, silica and zeolite.

### Claim 10 (depends on 1)

a process according to claim 1 wherein said oxygen-containing gas is air.

### Claim 11 (depends on 1)

A process according to claim 1 wherein said gas mixture contains 0.8-3 vol % of hydrogen sulfide.