Enhanced thermal and ignition stability azide gas generant
US5223184A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1991 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | Feb 6, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC06D5/06
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Multiple processes and apparatuses for improving the prior system of making gas generant pellets or tablets made of sodium azide, molybdenum disulfide and sulfur wherein powdered ingredients thereof are slurried in water, subjected to wet grinding, spray dried to a powdered material which is molded into pellets or tablets which find use in vehicle crash bags or inflators. The first improvement to the old process and apparatus involves adjusting the basicity of the water to a pH of greater than 8.0 up to about 12.5 via the addition of sodium hydroxide, followed by the addition of sulfur and molybdenum disulfide and finally the sodium azide whereby azide addition is made to a basic mixture of the other ingredients thereby keeping hydrazoic acid concentration levels below about 3.times.10EXP(-3) moles per liter. The second improvement to the old process and apparatus involves (1) softening the water before its use in slurrying the powdered ingredients to remove undesirable Ca and Mg ions and/or (2) adding sodium sulfide and/or tri-sodium phosphate to the slurry to precipitate any remaining undesirable Ca, Mg, Pb, Fe, Mn and Cu ions as non-hazardous compounds. Each of these metal ions …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.