RESEARCH PROCESSING OF SOLID PROPELLANT DISPOSAL PRODUCTS

Abstract

The disposal of expired ammunition, warheads, solid propellant rocket motors (SPRM) is a pressing ecological issue for today’s Ukraine. The process of disposal of solid propellant from loaded motor cases results in formation of polymer matrix with fragment sizes of of 2 mm to 15 mm that has found use as an energetic additive to make part of emulsion explosives (EE). The polymer matrix contains: a binder, an oxidizer (ammonium perchlorate), energetic additives (cyclic nitramine, i.e. cyclotetramethylenetetranitramine, and aluminium) and process additives. The first method  consists in the use of concentrated mineral acids and destruction of the binder. The major disadvantages of this method include large quantity of by-products and and process exothermicity with evolving toxic nitrogen oxides. The other method lies in selective extraction of cyclic nitramines from polymer matrix using organic solvents. To extract cyclic nitramine from solid propellant matrix from which ammonium perchlorate has been previously removed, a selective organic solvent - dimethyl sulphoxide can be used. At the preliminary stage of works, a water-soluble component, ammonium perchlorate, was extracted from polymer matrix, which is soluble both in dimethyl sulphoxide and in water, and therefore its presence as a strong oxidizing agent in the spent dimethyl sulphoxide solution in the case of dimethyl sulfoxide recovery is undesirable. Then, cyclic nitramine is extracted from the obtained polymer matrix with dimethyl sulphoxide, the solution is filtered off from refined polymer crumb, and cyclic nitramine is precipitated by adding a diluent, water, to the solution. The purpose of this work is to establish regularities of the extraction of cyclic nutramine from polymer matrix with the use of dimethyl sulphoxide in a laboratory environment with changing such parameter as mass module (dimethyl sulphoxide : polymer matrix ratio) dependence on polymer matrix moisture content. The most preferable mass module (dimethyl sulphoxide : polymer matrix ratio) can be considered a range of 2–3, which makes it possible to achieve a degree of cyclic nitramine recovery of 71.9% (with a moisture of polymer matrix - 3%). The identification of nitramine extracted from polymer matrix is confirmed by the IR spectrum the method of differential thermal analysis (DTA).