AMMONIA SEPARATION PROCESS

• US 3,607,047 A
• Filed: 06/25/1969
• Issued: 09/21/1971
• Est. Priority Date: 06/25/1969
• Status: Expired due to Term

• Current Assignee: Henry T. Broom, James O. Mcwhorter, Michael R. Basila
• Original Assignee: Henry T. Broom, James O. Mcwhorter, Michael R. Basila
• Inventors: Broom, Henry T., McWhorter, James O., Basila, Michael R.
• Primary Examiner(s): Friedman, Reuben
• Assistant Examiner(s): Burks, R. W.
• Application Number:
  US04/836,595
• Time in Patent Office: 818 Days
• Field of Search: 23/2,196 55/48,70
• US Class Current: 423/352
• CPC Class Codes: C01C 1/12 Separation of ammonia from gases and vapours as part of the ammonia synthesis process C01C1/04

Abstract

Ammonia is separated from a mixture containing ammonia and at least one of hydrogen sulfide and carbon dioxide, e.g., a coal gas, by a process comprising contacting the mixture with a phenolic liquid, e.g., cresols, for a time sufficient to provide a ratio of total moles of ammonia absorbed by the liquid to moles of phenolic in the liquid between 0.5 and 1.0, and thereafter separating the resulting mixture from the resulting phenolic liquid.

Claims

2. A process as defined in claim 1 wherein the temperature is between about 70*and 175* F.

3. A process as defined in claim 2 wherein the mixture is a gaseous mixture.

4. A process as defined in claim 3 wherein the mixture contains minor amounts of hydrocarbons, mercaptans and other weak acids.

5. A process as defined in claim 4 wherein the mixture is a gaseous mixture consisting essentially of ammonia and hydrogen sulfide with minor amounts of hydrocarbons, mercaptans and other week acids.

6. A process as defined in claim 5 wherein the phenolic mixture is at least one of phenol;

an alkyl phenol having up to six carbon atoms in the alkyl group; and

alkoxy phenol having up to about six carbon atoms in the alkoxy group;

a halophenol;

a hydroxyphenol;

naphthol; and

a xylenol.

7. A process as defined in claim 6 wherein the phenolic liquid is substantially a mixture of phenol and the cresols.

8. A process as defined in claim 7 wherein the phenolic liquid and the mixture are substantially anhydrous.

9. A continuous process for separating ammonia from a gaseous mixture containing ammonia and at least one of hydrogen sulfide and carbon dioxide which comprises countercurrently contacting a gaseous mixture having a temperature between about 70* and 130* F. with a phenolic liquid having a temperature between about 100*and 160* F. for a time sufficient to provide a ratio of total moles of ammonia absorbed by the liquid between 0.5 and 1.0;

thereafter separating the resulting substantially ammonia-free gaseous mixture from the resulting phenolic liquid containing absorbed ammonia;

heating the phenolic liquid containing ammonia so as to remove substantially all of the ammonia from the liquid; and

then using the phenolic liquid from which ammonia has been removed as a recycle stream.

10. A process as described in claim 9 which contains the additional step of using a portion of the resulting phenolic liquid containing absorbed ammonia as a recycle stream so as to keep the temperature of reaction between ammonia and phenolic liquid between about 95* and 175* F.