JP2014031284A - Production method of rdx - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of RDX in which a content of HMX is made few, thereby fastening of a crystal of the HMX to an inner wall of a crystallization tank is made few, and secular change of impact sensitivity is made few.SOLUTION: A production method of RDX is configured such that a solution in which ammonium nitrate is dissolved in concentrated nitric acid, a solution in which hexamethylene tetramine is dissolved in acetic acid, and acetic acid anhydride are made a raw material, the raw material is performed by nitration, then added by water to be subjected to hydrolysis, subjected to filtration to separate waste acid, then subjected to water washing, next crude RDX obtained by performing wash boiling is dissolved by an organic solvent to perform crystallization, performed by water washing, then is filtered to perform recrystallization, and the production method of RDX is characterized in that a particle of 74-125 μm in the RDX subjected to crude crystallization and/or recrystallization is removed.

Description

  The present invention relates to a method for producing hexogen (hereinafter referred to as RDX) which is a main component of an explosive composition.

  One method for producing RDX is the acetic acid method. In this method, as shown in FIG. 1, a solution in which ammonium nitrate is dissolved in concentrated nitric acid, a solution in which hexamethylenetetramine (hexamine) is dissolved in acetic acid, and acetic anhydride as a raw material are nitrated. In addition, hydrolysis, filtration to separate the waste acid, followed by washing with water, followed by boiling and washing to obtain a crude RDX dissolved in an organic solvent, crystallization, washing with water and filtration to obtain recrystallized RDX The RDX obtained by this method contains octogen (hereinafter referred to as HMX) 4 to 15% (applicable standard: TL-1376-802) according to the standard.

  In recent years, development of nitramine-based propellants has been promoted in order to increase energy and safety, but when RDX by the acetic acid method is used as a propellant raw material, Depending on the type, the solubility of HMX is lower than that of RDX, so that when crystallizing, HMX crystals are precipitated in the crystallizer before RDX, causing sticking to the inner wall of the crystallization tank, resulting in poor working efficiency. . Also, there is a report that the HMX content contained even in the acetic acid method RDX in which the impact sensitivity is desensitized causes the secular change of the impact sensitivity to occur, and if the HMX in the RDX decreases, the secular change will occur. It is thought that the possibility of becoming difficult becomes high.

  This invention is made | formed in view of this point, and it aims at providing the manufacturing method of RDX of a grade with few HMX content.

  The inventors of the present invention measured the HMX content for each grain size of the RDX of the crude crystal and the recrystallized product.

  Table 1 and FIG. 2 show the HMX content (%) for each particle size distribution in the sample 1-3 of the crude crystal RDX, and Table 2 and FIG. 3 show each particle size distribution in the sample 1-3 of the recrystallized RDX. This shows the HMX content (%).

  From the above measurement results, the present inventors have found that the RDX of the crude crystal product and the recrystallized product has a high HMX content when the particle size is 74 to 125 μm or less, particularly 74 μm or less.

  The present invention has been made on the basis of such knowledge. A solution in which ammonium nitrate is dissolved in concentrated nitric acid, a solution in which hexamine is dissolved in acetic acid, acetic anhydride as a raw material, which is nitrated and added with water. Hydrolyzed, separated by filtration and washed with water, then boiled and washed to dissolve the crude RDX with an organic solvent, crystallized, washed with water, filtered and recrystallized. In the production method, particles of 74 to 125 μm or less, preferably 74 μm or less, are removed from the crude crystals and / or recrystallized RDX.

  According to the method of the present invention, RDX having an HMX content of less than 4% can be obtained.

The flowchart which shows the conventional acetic acid method RDX manufacturing method. The graph which shows HMX content for every particle size distribution of a coarse crystal product. The graph which shows HMX content for every particle size distribution of a recrystallized product. The flowchart which shows the RDX manufacturing method which concerns on this invention.

  FIG. 4 shows a method for producing RDX according to the present invention. The difference from the conventional method shown in FIG. In the point which newly provided the process to remove, the coarse RDX on a sieve is recrystallized in the same process as the conventional method.

  According to the production method of the present embodiment, RDX having an HMX content of 0.5 to 1.2% can be obtained.

Claims (2)

  A solution in which ammonium nitrate is dissolved in concentrated nitric acid, a solution in which hexamethylenetetramine is dissolved in acetic acid, and acetic anhydride as a raw material, which is nitrated, hydrolyzed with water, and filtered to separate waste acid Then, the crude RDX obtained by washing with water and then boiled is dissolved in an organic solvent to crystallize, washed with water, filtered and recrystallized. A method for producing RDX, wherein particles of 74 to 125 μm or less are removed from RDX.   The method for producing RDX according to claim 1, wherein the particles to be removed are 74 µm or less.