POWDER FOR EXTINGUISHING FIRES Russian patent published in 1997 - IPC

FIELD: fire fighting. SUBSTANCE: fire extinguishing powder compositions are provided that may be used to smother various-type fires including those in closed spaces. Powder is a multiphase disperse-reinforced composite material, monolithic state of each particle of which is caused be chemical interaction between contained therein phases: complex hydroxide [M(II)_xAl(III)_yM(IV)_z(OH)_(2x+3y+4z)] and phases [M(I)An₁] and [M(I)An₂] where M(I) is Li, Na, K, Rb, Cs, NH₄, or their mixture; M(II) is Mg, Ca, Zn, or their mixture; M(IV) is Si, Ti, Zr, or their mixture; An₁ is F, Cl, Br, I; An₂ nitrate, perchlorate, sulfate, carbonate, or phosphate groups; x ranges from 20 to 1; y from 1 to 10; z from 0 to 10; a from 100 to 1; and b from 1 to 30. All particles of powder have the same chemical and phase composition, each phase being active with regard to fire extinguishing. Powder is prepared by adding alkali metal or ammonium hydroxide aqueous solution to aqueous solution with predetermined molar proportion of M(II), Al(III), and M(IV) at room temperature, whereupon water is stripped off by a conventional technique. Prepared fire extinguishing powder is a running substance with spherical particles, 40-70 mcm fraction constituting at least 95 wt %. EFFECT: improved fire-extinguishing characteristics. 2 cl, 1 tbl