Precipitation method and synthesis method of 2,6-diamino-3,5-dinitropyrazine-1-oxide

Patent metadata

Field	Value
Publication number	US-10836731-B2
Application number	US-201816488056-A
Country	US
Kind code	B2
Filing date	Feb 26, 2018
Priority date	Feb 28, 2017
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

A method for precipitating as particles 2,6-diamino-3,5-dinitropyrazine-1-oxide (or ANPZO) present in an acid medium, which comprises adding the acid medium to an aqueous solution and which is characterized in that the aqueous solution comprises a nitrate salt. Further disclosed is a method for synthesizing ANPZO implementing this precipitation method. The synthesis method comprises converting 2,6-diaminopyrazine-1-oxide (or DAPO) into ANPZO by nitration in an acid medium, and then precipitating as particles the ANPZO by adding the acid medium to an aqueous solution, and is characterized in that the aqueous solution comprises a nitrate salt.

First claim

What is claimed is:

1. A method for precipitating as particles 2,6-diamino-3,5-dinitropyrazine -1-oxide present in an acid medium, the medium comprising nitric acid or a nitrate salt or a mixture thereof, and at least one strong acid other than nitric acid, the method comprising adding the acid medium to an aqueous solution comprising a nitrate salt; and precipitating as particles 2,6-diamino-3,5-dinitropyrazine-1-oxide.

2. A method for synthesizing particles of 2,6-diamino-3,5-dinitropyrazine -1-oxide, comprising:
converting 2,6-diaminopyrazine-1-oxide into 2,6-diamino-3,5-dinitroyrazine-1-oxide by nitrating 2,6-diaminopyrazine-1-oxyde in an acid medium comprising nitric acid or a nitrate salt or a mixture thereof, and at least one strong acid other than nitric acid, and then
precipitating as particles 2,6-diamino-3,5-dinitropyrazine-1-oxide by adding the acid medium to an aqueous solution comprising a nitrate salt.

3. The method of claim 1 , wherein the nitrate salt is sodium nitrate, potassium nitrate or ammonium nitrate.

4. The method of claim 1 , wherein the aqueous solution comprises between 110 g and 2,500 g of the nitrate salt for 1 litre of water.

5. The method of claim 1 , wherein a ratio of a volume of the aqueous solution to a volume of the acid medium is comprised between 0.5 and 10.

6. The method of claim 1 , wherein the acid medium is gradually added to the aqueous solution.

7. The method of claim 1 , further comprising collecting the particles, washing the particles and drying the particles.

8. The method of claim 2 , wherein converting 2,6-diaminopyrazine -1-oxide into 2,6-diamino-3,5-dinitropyrazine-1-oxide comprises:
forming a reaction medium by adding nitric acid or a nitrate salt or a mixture thereof to a solution comprising 2,6-diaminopyrazine-1-oxide in at least one strong acid other than nitric acid; and
maintaining the reaction medium under stirring.

9. The method of claim 1 , wherein the strong acid other than nitric acid is sulfuric acid.

10. The method according to claim 9 , wherein the acid medium comprises nitric acid and sulfuric acid.

11. The method of claim 2 , wherein the nitrate salt is sodium nitrate, potassium nitrate or ammonium nitrate.

12. The method of claim 2 , wherein the aqueous solution comprises between 110 g and 2,500 g of the nitrate salt for 1 litre of water.

13. The method of claim 2 , wherein a ratio of a volume of the aqueous solution to a volume of the acid medium is comprised between 0.5 and 10.

14. The method of claim 2 , wherein the acid medium is gradually added to the aqueous solution.

15. The method of claim 2 , further comprising collecting the particles, washing the particles and drying the particles.

16. The method of claim 2 , wherein the strong acid other than nitric acid is sulfuric acid.

17. The method according to claim 16 , wherein the acid medium comprises nitric acid and sulfuric acid.

Assignees

• Commissariat Energie Atomique

Inventors

• Pasquinet Eric
• Wuillaume Anne
• Pin Nicolas
• Beaucamp Arnaud
• Barthet Christelle

Classifications

• C07D241/20 Primary

  Nitrogen atoms (nitro radicals C07D241/16) · CPC title

• C07D241/16 Primary

  Halogen atoms; Nitro radicals · CPC title

• B01D9/02

  from solutions · CPC title

• B01D2009/009

  Separation of organic compounds by selective or extractive crystallisation with the aid of auxiliary substances forming complex or molecular compounds, e.g. with ureum, thioureum or metal salts · CPC title

• B01D9/005

  Selection of auxiliary, e.g. for control of crystallisation nuclei, of crystal growth, of adherence to walls; Arrangements for introduction thereof · CPC title