High temperature two component explosive

• US 4,274,893 A
• Filed: 03/26/1979
• Issued: 06/23/1981
• Est. Priority Date: 03/26/1979
• Status: Expired due to Term

• Current Assignee: Rocket Research Company
• Original Assignee: Rocket Research Company
• Inventors: Poole, Donald R., Schmidt, Eckart W., Wang, Charles, Mars, James E.
• Primary Examiner(s): Lechert, Jr., Stephen J.
• Application Number:
  US06/023,786
• Time in Patent Office: 820 Days
• Field of Search: 149/21, 149/45, 149/61, 149/83, 149/70, 149/2, 149/74, 149/92
• US Class Current: 149/2
• CPC Class Codes: C06B 47/00 Compositions in which the components are separately stored until the moment of burning or explosion, e.g. "Sprengel"-type explosives; Suspensions of solid component in a normally non-explosive liquid phase, including a thickened aqueous phase

Abstract

A two component, high temperature, thermally stable explosive composition comprises a liquid or low melting oxidizer and a liquid or low melting organic fuel. The oxidizer and fuel in admixture are incapable of substantial spontaneous exothermic reaction at temperatures on the order of 475° K. At temperatures on the order of 475° K., the oxidizer and fuel in admixture have an activation energy of at least about 40 kcal/mol. As a result of the high activation energy, the preferred explosive compositions are nondetonable as solids at ambient temperature, and become detonable only when heated beyond the melting point. Preferable oxidizers are selected from alkali or alkaline earth metal nitrates, nitrites, perchlorates, and/or mixtures thereof. Preferred fuels are organic compounds having polar hydrophilic groups. The most preferred fuels are guanidinium nitrate, acetamide and mixtures of the two. Most preferred oxidizers are eutectic mixtures of lithium nitrate, potassium nitrate and sodium nitrate, of sodium nitrite, sodium nitrate and potassium nitrate, and of potassium nitrate, calcium nitrate and sodium nitrate.

Claims

1. A high temperature, thermally stable explosive composition comprising:

a low melting oxidizer selected from the group consisting of nitric acid, alkali or alkaline earth metal nitrates, nitrites, perchlorates and mixtures thereof,

a liquid or low melting organic fuel, said fuel and said oxidizer in admixture being thermally stable at temperatures on the order of 475°

K. and having a relatively high energy of activation at temperatures on the order of 475°

K.

2. The explosive composition of claim 1 wherein said fuel and said oxidizer in admixture are thermally stable at temperatures on the order of 500°

K.

3. The explosive composition of claim 1 wherein said fuel and said oxidizer in admixture have an energy of activation of at least 40 kcal/mol at temperatures on the order of 475°

K.

4. The explosive composition of claim 1 wherein said fuel and said oxidizer in admixture do not spontaneously exothermically react at a temperature of about 500°

K.

5. The explosive composition of claim 1 wherein said oxidizer and said fuel are miscible.

6. The explosive composition of claim 1 wherein said fuel contains polar hydrophilic groups.

7. The explosive composition of claim 6 wherein said polar hydrophilic groups are selected from the group consisting of hydroxy, carboxy, carboxy ester, imido, amido, sulfone, sulfoxy, guanidinium, carboxy acid ester, ether and nitrile groups.

8. The explosive composition of claim 1 wherein said oxidizer and said fuel are at least partially immiscible, said explosive composition further comprising a gelling agent to inhibit separation of said oxidizer and said fuel upon standing.

9. The explosive composition of claim 8 wherein said gelling agent is fumed silica.

10. The explosive composition of claims 1, 5 or 8 further comprising a metal powder added to said oxidizer and to said fuel to increase the heat of explosion thereof.

11. The explosive composition of claim 10 further comprising a gelling agent to prevent the metal powder from separating upon standing.

12. The explosive composition of claim 11 wherein said gelling agent is fumed silica.

13. The explosive composition of claims 1, 5 or 8 further comprising glass or quartz microballoons to enhance detonability under high pressure.

14. The explosive composition of claim 13 further comprising a gelling agent to maintain said microballoons in suspension.

15. The explosive composition of claim 14 wherein said gelling agent is fumed silica.

16. The explosive composition of claim 1 wherein said oxidizer is selected from low melting mixtures of the group consisting of lithium, sodium, potassium, magnesium, and calcium perchlorate, and mixtures thereof.

17. The explosive composition of claim 1 wherein said oxidizer is selected from the group consisting of a eutectic mixture of lithium nitrate, potassium nitrate, and sodium nitrate;

a eutectic mixture of sodium nitrite, sodium nitrate and potassium nitrate; and

a eutectic mixture of potassium nitrate, calcium nitrate and sodium nitrate.

18. The explosive composition of claim 17 wherein said oxidizer further comprises up to about 30% by weight based on the initial oxidizer present in said explosive composition of a member of the group consisting of lithium, sodium, potassium, magnesium, calcium perchlorate, and mixtures thereof.

19. The explosive composition of claims 3, 4, 5, 8, 16, 17 or 18 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

20. The explosive composition of claim 19 wherein said fuel comprises a mixture of from 70% to 99% of guanidinium nitrate and from 1% to 30% acetamide, the weight percentages being based on the total amount of fuel present in said explosive composition.

21. The explosive composition of claim 19 wherein said oxidizer is a eutectic mixture of sodium, potassium, and calcium nitrates, and said fuel is a mixture of about 70% by weight of guanidinium nitrate and about 30% by weight acetamide, said weight percentages herein based upon the total amount of fuel present in said explosive composition.

22. The explosive composition of claim 21 wherein said oxidizer comprises about 58.7% by weight of the total oxidizer and fuel present in said explosive composition and wherein said fuel comprises about 41.3% by weight of the total oxidizer and fuel present in said explosive composition.

23. The explosive composition of claim 22 further comprising sodium perchlorate present in an amount up to about 30% by weight based on the inital amount of oxidizer present in said explosive composition.

24. The explosive composition of claims 1, 3, 4, 5, 8, 16, 17 or 18 wherein said fuel is selected from the group consisting of formamide, N,N-dimethyl formamide, N-methyl acetamide, N,N-dimethyl acetamide, dimethyl sulfoxide, melamine, a mixture of melamine and guanidinium nitrate, a mixture of melamine and acetamide, a mixture of melamine and N-methyl-2-pyrrolidone, pentaerythritol, tetrahydrothiophene-1,1-dioxide, N-methyl-2-pyrrolidone, diphenyl ether, diphenyl sulfone, diphenyl sulfoxide, triphenyl phosphate, polyphenyl ether, phthalic anhydride, phthalimide, phthalonitrile, phthalocyanine, a mixture of phthalonitrile and phthalocyanine, dimethylphthalate, dibutyl phthalate, triacetin, and mixtures thereof.

25. The explosive of claims 1, 17 or 18, wherein said explosive composition is a solid and is nondetonable at ambient temperatures and is detonable when heated to temperatures above the melting point of said composition.

26. A method for emplacing an explosive in a borehole comprising the steps of:

separately passing a low melting oxidizer and a liquid or low melting organic fuel down said borehole, said oxidizer being selected from the group consisting of nitric acid, alkali or alkaline earth metal nitrates, perchlorates and mixtures thereof, said fuel and said oxidizer in admixture being thermally stable at temperatures on the order of 475°

K. and having a relatively high energy of activation at temperatures on the order of 475°

K.,

mixing said oxidizer and said fuel downhole to form a detonable mixture, and

detonating said mixture.

27. The method of claim 26, wherein said oxidizer and said fuel are separately pumped down said borehole.

28. The method of claim 26, wherein said oxidizer and said fuel are placed in containers aboveground and passed separately down said borehole.

29. The method of claim 26, wherein said borehole communicates with a geothermal formation.

30. The method of claim 26, wherein the reaction products formed by detonation of said mixture are alkaline, the method further comprising the step of allowing said products to remain in said geothermal formation for a substantial period of time after said mixture is detonated.

31. The method of claim 26, wherein a container having at least one conical indentation is first emplaced in said borehole, said oxidizer and said fuel then being separately passed down said borehole and mixed in said container before detonation.

39. The method of claim 26 wherein said fuel and said oxidizer in admixture have an energy of activation of at least 40 kcal/mol at temperatures on the order of 475°

K.

40. The method of claim 26 wherein said fuel and said oxidizer in admixture do not spontaneously exothermically react at a temperature of about 500°

K.

41. The method of claim 26 wherein said oxidizer is selected from low melting mixtures of the group consisting of lithium, sodium, potassium, magnesium, and calcium perchlorate, and mixtures thereof.

42. The method of claim 26 wherein said oxidizer is selected from the group consisting of a eutectic mixture of lithium nitrate, potassium nitrate, and sodium nitrate;

a eutectic mixture of sodium nitrite, sodium nitrate, and potassium nitrate; and

a eutectic mixture of potassium nitrate, calcium nitrate, and sodium nitrate.

43. The method of claim 26 wherein said oxidizer further comprises up to about 30% by weight based on the initial oxidizer present in said explosive composition of a member of the group consisting of lithium, sodium, potassium, magnesium, calcium, perchlorate, and mixtures thereof.

44. The method of claim 41 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

45. The method of claim 42 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

32. A method for emplacing an explosive in a borehole comprising the steps of:

mixing and melting a liquid or low melting organic fuel and a low melting oxidizer to form a mixture, said oxidizer being selected from the group consisting of nitric acid, alkali or alkaline earth metal nitrates, perchlorates and mixtures thereof, said fuel and said oxidizer in admixture being thermally stable at temperatures on the order of 475°

K. and having a relatively high energy of activation at temperatures on the order of 475°

K.,

allowing said mixture to solidify to form a solid, nondetonable, material,

passing said material down said borehole wherein indigenous heat remelts said mixture to form a detonable composition.

33. The method of claim 32, wherein said borehole communicates with a geothermal formation.

34. The method of claim 32, wherein the reaction products formed by detonation of said mixture are alkaline, the method further comprising allowing said products to remain in said geothermal formation for a substantial period of time after said mixture is detonated.

35. The method of claim 32, wherein said material is placed in a container having at least one conical indentation, and then passed down said borehole in said container.

46. The method of claim 32 wherein said fuel and said oxidizer in admixture have an energy of activation of at least 40 kcal/mol at temperatures on the order of 475°

K.

47. The method of claim 32 wherein said fuel and said oxidizer in admixture do not spontaneously exothermically react at a temperature of about 500°

K.

48. The method of claim 32 wherein said oxidizer is selected from low melting mixtures of the group consisting of lithium, sodium, potassium, magnesium, and calcium perchlorate and mixtures thereof.

49. The method of claim 32 wherein said oxidizer is selected from the group consisting of a eutectic mixture of lithium nitrate, potassium nitrate, and sodium nitrate;

a eutectic mixture of sodium nitrite, sodium nitrate, and potassium nitrate; and

a eutectic mixture of potassium nitrate, calcium nitrate, and sodium nitrate.

50. The method of claim 32 wherein said oxidizer further comprises up to about 30% by weight based on the initial oxidizer present in said explosive composition of a member of the group consisting of lithium, sodium, potassium, magnesium, calcium perchlorate, and mixtures thereof.

51. The method of claim 48 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

52. The method of claim 49 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

36. A method of using an explosive composition comprising the steps of

combining a low melting oxidizer and a liquid or low melting organic fuel to form a detonable mixture, said oxidizer being selected from the group consisting of nitric acid, alkali or alkaline earth metal nitrates, perchlorates and mixtures thereof, said fuel and said oxidizer in admixture being thermally stable at temperatures on the order of 475°

K. and having a relatively high energy of activation at temperatures on the order of 475°

K.,

allowing the temperature of said mixture to rise to greater than 475°

K., and

detonating said mixture.

53. The method of claim 36 wherein said fuel and said oxidizer in admixture have an energy of activation of at least 40 kcal/mol at temperatures on the order of 475°

K.

54. The method of claim 36 wherein said fuel and said oxidizer in admixture do not spontaneously exothermically react at a temperature of about 500°

K.

55. The method of claim 36 wherein said oxidizer is selected from low melting mixtures of the group consisting of lithium, sodium, potassium, magnesium, and calcium perchlorate, and mixtures thereof.

56. The method of claim 36 wherein said oxidizer is selected from the group consisting of a eutectic mixture of lithium nitrate, potassium nitrate, and sodium nitrate;

a eutectic mixture of sodium nitrite, sodium nitrate, and potassium nitrate; and

a eutectic mixture of potassium nitrate, calcium nitrate, and sodium nitrate.

57. The method of claim 36 wherein said oxidizer further comprises up to about 30% by weight based on the initial oxidizer present in said explosive composition of a member of the group consisting of lithium, sodium, potassium, magnesium, calcium perchlorate, and mixtures thereof.

58. The method of claim 55 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

59. The method of claim 56 wherein said fuel is selected from the group consisting of acetamide, guanidinium nitrate, and mixtures thereof.

37. A high temperature, thermally stable explosive composition comprising

a low melting oxidizer in admixture with liquid or low melting organic fuel, said oxidizer and fuel being incapable of substantial, spontaneous exothermic reaction at temperatures on the order of 475°

K., and having an activation energy of at least 40 kcal/mol.

38. The explosive composition of claim 37 wherein said oxidizer and said fuel in admixture are incapable of substantial, spontaneous, exothermic reaction at temperatures on the order of 500°

K. and have an activation energy at temperatures on the order of 500°

K. of at least about 40 kcal/mol.