Method of making monoammonium salt of 5,5′-bis-1H-tetrazole
View Patent ↗A method of forming monoammonium salt of 5,5′-bis-1H-tetrazole (BTA-1NH3) is presented comprising the steps of charging a mixing vessel with a solution of free BTA acid and distilled water, adding ammonium hydroxide in excess to obtain a pH of at least 9.5 and mixing the solution, and adding sulfuric acid cooled to 10-20 degrees Celsius to obtain a pH of at least 4.5 and mixing the solution. A gas generator 10 containing a gas generant 12 containing the BTA-1NH3 formed in accordance with the present invention is also presented. Gas generating systems 180 such as vehicle occupant protection systems 180 , containing the gas generator 10 , are also provided.
1. A method of forming the monoammonium salt of 5,5′-bis-1H-tetrazole comprising the steps of:
charging a mixing vessel with a solution of free 5,5′-bis-1H-tetraole acid and distilled water;
ammoniating the solution to obtain a pH of at least 9.5 and mixing the solution; and
acidifying the solution while cooling the solution to 5-20 degrees Celsius, to obtain a pH of at least 4.5 and precipitate a solid.
2. The method of claim 1 wherein the ammoniating step comprises adding ammonium hydroxide while heating the solution to about 65-70 C.
3. The method of claim 1 wherein the acidifying step comprises adding 33% sulfuric acid solution to the solution.