Preparing RDX

The beginning of explosive is 170°C by using Fulminate or Azide detonator but it can cannot Be exploded by fire and it can be used as a booster for compound detonator. 

Nitric Acid (HNO3) cone. 85% + Hexamine (C6H12N4) Water 

120ml of strong Nitric Acid (HNO3) place in the beaker and drop the temperature between 20-30°C. The temperature must be controlled by the hot and cold water bath. 

Add 70gm of Hexamine (C6H12N4) to the acid 1/2 teaspoon at a time with 15 minutes gap, shaking gently continuously. It will normally take 3 hours to complete addition of Hexamine (C6H12N4) in the acid. 

After all Hexamine (C6H12N4) has dissolved in the acid raise the temperature up to 55°C and maintain this temperature for 10 minutes. 

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Herz succeeded in preparing RDX by direct nitration of hexamine, but the yields were low and the process was expensive and unattractive for large scale production. Hale, at Picatinny Arsenal in 1925, developed a process for manufacturing RDX which produced yields of 68%. However, no further substantial improvements were made in the manufacture of RDX until 1940 when Meissner developed a continuous method for the manufacture of RDX, and Ross and Schiessler from Canada developed a process which did not require the use of hexamine as a starting material. At the same time, Bachmann developed a manufacturing process for RDX (1.5) from hexamine which gave the greatest yield. 

The simplest method of preparing RDX (7.9) is by adding hexamethylenetetramine to excess concentrated nitric acid at 25 °C and warming to 55 °C. RDX is precipitated with cold water and the mixture is then boiled to remove any soluble impurities. Purification of RDX is carried out by recrystallization from acetone. 

RDX , OSRD Rept 159 (Oct 1941) 28) F.C. Whitmore, "Recovery of Acetic Acid and Ammonium Nitrate from the Bachmann Process for Preparing RDX , OSRD Rept 393 (Feb 1942)... 

Hexogen (RDX) was first prepared in 1899 by Henning for medicinal use. (N.B. NG and PETN are also used in medicine to treat angina pectoris. The principal action of these nitrate esters is vasodilation (i.e. widening of the blood vessels). This effect arises because in the body the nitrate esters are converted to nitric oxide (NO) by mitochondrial aldehyde dehydrogenase, and nitric oxide is a natural vasodilator.) In 1920 Herz prepared RDX for the first time by the direct nitration of hexamethylene tetramine. Shortly afterwards Hale (Picatinny Arsenal, NJ) developed a process that formed RDX in 68 % yield. The two processes most widely used in WW II were... 

W. E. Bachmann and Sheehan [158] developed a method of preparing RDX containing a small quantity of HMX. The method involved niirolysis of hex-amine with ammonium nitrate-nitric acid solution and acetic anhydride. By varying parameters of temperature and acid concentration, ammonium nitrate and acetic anhydride it wa.s shown that the ratio RDX/IIMX can be altered. These results led Bachmann and co-workeis to prepare mixture rich in HMX. Die optimum yield obtained was 82% conversion of hexamine to HMX/RDX mixture containing up to 73% HMX. 

The standard normally employed is a specially prepared RDX having an assigned FI of 80. 

Most of the AFM data presented here is on shocked or impacted crystals of the explosive RDX. Other explosives have been examined to lesser degrees and these show similar results to RDX. Because RDX is a non-conducting molecular crystal the AFM must be used to examine its deformation properties. For contrast with a very different material the results of a series of impacts on gold are also presented. Prior to shock or impact AFM and STM observations were made on well prepared RDX crystals and gold samples. These yielded the known molecular and lattice stmctures of RDX and the lattice stmcture of gold. 

Before proceeding to describe the manufacture of the nitramines, RDX and Tetryl, a few general remarks about the preparation of nitramines... 

A linear relationship between Chapman-Jouguet pressure and density was confirmed for Cyclotol and Octol (Ref 28). Despite the near-equal performance of RDX and HMX at equal densities there appears to be no economical way of making the density of RDX equal to the cast density of HMX. Dinitrobenzene (DNB) has been evaluated as an economical or emergency substitute for TNT but charges prepared with DNB gave somewhat poorer performance than... 

Plastic-Bonded RDX, Its Preparation By the Slurry Method , Holston Defense Corp, Term, Control No 20-T-16 Series A (PAC 1081) (1953) 8) A.J. Pascazio, The Suitability of a Bare PBX Booster Pellet In The 2.75-Inch HEAT Ml Rocket Head , PATR 2271 (1955) 9) H.W. 

All reagents and solvents were used as received (Sigma-Aldrich) if not stated otherwise. NOL-130 stab initiation mix and preformed, 19 mg graphite-blended l,3,5-trinitro-l,3,5-triazacyclohexane (RDX) pellets were purchased from Day Zimmerman (DZI). Samples prepared for LC-MS analysis were dissolved in ammonium hydroxide and run utilizing a Phenomenex Gemini C6-Phenyl column (4.6 mm X 150 mm) and a mobile phase of 20 mM ammonium acetate in water pH 7.02 at 0.75 ml,-min The HPLC analysis is done using... 

Fluorescent cellulose triacetate membranes were prepared by incorporation of pyrene-butyric acid (219), and were applied to in situ detection of ground water contamination by explosives, based on fluorescence quenching by the nitro groups LOD 2 mg/L of DNT (220) and TNT (221) and 10 mg/L for RDX (276) the response follows the Stern-Volmer law for DNT and TNT442. 

In some related work, Lear and co-workers prepared the powerful cyclic nitramine explosive Keto-RDX (102) from the nitrolysis-nitration of2-oxa-5-tert-butyltriazone(101). Pagoria and co-workers " conducted a full study on the effect of different nitrating agents on the yield of Keto-RDX (Table 5.6). 

The most important nitrolysis reaction to date is the formation of RDX (3) and HMX (4) from the caged methylenediamine known as hexamine (104). These important military explosives were first mass manufactured by this route towards the end of the Second World War and they are still prepared by this route today. The process uses a mixture of acetic anhydride, ammonium nitrate and nitric acid. The nitrolysis of hexamine is one of the most widely studied reactions in the history of explosives. Many other cyclic and linear polynitramines have been isolated from these reactions and this rich chemistry is discussed in more detail in Section 5.15. 

The presence of HMX as an impurity in RDX is not a problem when the product is used as an explosive. However, the need for an analytical sample of RDX makes other more indirect methods feasible. One such method involves the oxidation of 1,3,5-trinitroso-1,3,5-triazacyclohexane (109) ( R-salt ) with a mixture of hydrogen peroxide in nitric acid at subambient temperature and yields analytical pure RDX (74%) free from HMX." The same conversion has been reported in 32 % yield with three equivalents of a 25 % solution of dinitrogen pentoxide in absolute nitric acid. l,3,5-Trinitroso-l,3,5-triazacyclohexane (109) is conveniently prepared from the reaction of hexamine with nitrous acid at high acidity. ... 

The nitrolysis of hexamine is a direct route to the military high explosives 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and l,3,5,7-tetranitro-13,5,7-tetraazacyclooctane (HMX). " The direct nitrolysis of hexamine with dinitrogen pentoxide in absolute ifitric acid provides RDX in 57 % yield. RDX prepared by this process is exceptionally pure, but other reagents, like ammonium nitrate-nitric acid-acetic anhydride, give much higher yields, partly because they use ammonium nitrate to supplement for ammonium nitrogen deficiency in the reaction. 

We hired them a chemical laboratory on the CSIR site, and they proceeded to prepare vapor samples using a technique of adsorptions onto polyethylene beads and a split-dilute-equilibrate-split again, etc., till they got down to vapor concentration levels of 10-14 grams RDX (cyclotrimethylenetrinitrzmine). This was the technique they had used to evaluate other chemical systems, like the Condor system. 

Hexamine serves as a parent compound for the preparation of RDX, HMX Hexamethyl-enetriperoxidediamine. It is also used in a mixture with sodium phenate, as an adsorbent of phosgene in gas masks. Its use as a cross-linking agent for guar gum in AN-slurry explosives has been patented (Refs 9 10)... 

The simplest method to prepare blends of RDX TNT is to dissolve them in acetone and precipitate the powder by adding cold water... 

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