PETN manufacture

For PETN manufacture the pentaerythritol starting material can be readily purchased as a commodity chemical from commercial suppliers. The nitration is relatively simple, involving only nitric acid (96-98%) and the... 

KNAUERIT SPECIAL is the trade name of a high-power plastic explosive based on -> PETN, manufactured by the DYNAMIT NOBEL VIENNA Company. 

Ramaswamy and Subba Rao suggested two methods of stabilizing the spent acid of PETN manufacture. 

Now let s look more closely at the first stage of PETN manufacture, making pentaerythritol. This adventure in chemistry is custom made for those who like to handle large volumes of really revolting chemicals and do endless hours of labor to get a quantity of product measured in fractions of a pound. Look once again at the materials covered earlier in this book. 

Compared to making pentaerythritol, PETN manufacture is a breeze. The amount of labor in the process is much less, and the volumes of chemicals which need to be handled are trivial in comparison. 

Relatively little can be added to the description of the methods of PETN manufacture Continuous methods are mostly used in modern plants (see also Pig. 74. Vol. II. p. 188). 

While PETN can be manufactured by treating pentaerythritol with nitric acid and adding concentrated sulfuric acid to complete the separation of the PETN, manufacture in the United States has been with nitric acid alone ... 

For PETN manufacture the pentaerythritol starting material can be readily purchased as a commodity chemical from commercial... 

Only relatively few compounds can act as primary explosives and still meet the restrictive military and industrial requirements for reflabiUty, ease of manufacture, low cost, compatibiUty, and long-term storage stabiUty under adverse environmental conditions. Most initiator explosives are dense, metaHoorganic compounds. In the United States, the most commonly used explosives for detonators include lead azide, PETN, and HMX. 2,4,6-Triamino-l,3,5-triuitrobenzene (TATB) is also used in electric detonators specially designed for use where stabiUty at elevated temperatures is essential. 

Lead Azide. The azides belong to a class of very few useflil explosive compounds that do not contain oxygen. Lead azide is the primary explosive used in military detonators in the United States, and has been intensively studied (see also Lead compounds). However, lead azide is being phased out as an ignition compound in commercial detonators by substances such as diazodinitrophenol (DDNP) or PETN-based mixtures because of health concerns over the lead content in the fumes and the explosion risks and environmental impact of the manufacturing process. 

From about 1930 onwards a new type of detonating fuse appeared on the market. This consisted of a core of PETN with textile and plastic coatings. Compared with Cordeau, this detonating fuse has several advantages in being more flexible, more easily jointed, lighter in weight and cheaper to manufacture. Under such names as Cordtex and Primacord it has completely replaced Cordeau in normal use. 

The PETN must be sufficiently fine to propagate reliably in small diameter at the same time it must be relatively free flowing. These two properties are to some extent contradictory, but suitable grades can be manufactured by careful attention to the method of precipitating the PETN during purification. 

The velocity of detonation of a fuse is about 6500 m s-1. This is attained in the dry process by adequate consolidation of the core during manufacture. During the wet process the necessary density is attained automatically by the method of preparing the core. Fuse usually contains about 10 g PETN per metre length. 

The first type to be introduced consisted of PETN or RDX in a metal sheath drawn down to a small diameter. More recently, cord made by the wet process, covered with plastic instead of metal, has been introduced in North America and is available in charges down to 0-6 g m. The methods of manufacture of these cords are believed to be similar to that of Cordeau and the wet detonating fuse process described above. 

Detonating Cord core of pentaerythritol tetra-nitrate (PETN) contained within a waterproof covering of textile or plastic available in several grades, each on spools of 500 or 1,000 feet. Manufactured by the Ensign-Bickford Company, Coast Fuse, Inc and Austin Powder Company SAFETY FUSE... 

Pentaerythritol is made by mixing formaldehyde with calcium hydroxide in an aqueous solution held at 65-70 °C. Nitration of pentaerythritol can be achieved by adding it to concentrated nitric acid at 25-30 °C to form PETN. The crude PETN is removed by filtration, washed with water, neutralized with sodium carbonate solution and recrystallized from acetone. This manufacturing process for PETN results in 95% yield with negligible by-products. The process is summarized in Reaction 7.9 (overleaf). 

Adds Used In Manufacture and Analyses of Explosives. Most expls (such as PA, TNT, PETN, NG, etc) are prepd by treating org compds with nitric acid in the presence of sulfuric acid or oleum, which binds the H,0 formed during the nitration reaction. Thus, the prepn of NG may be written as fellows ... 

Of the various methods of manufacturing PETN, the most widely used involves pouring pentaerythritol into nitric acid (d — 1.50-1.52) at a temperature not exceeding 25°C. PETN is scarcely soluble in nitric acid. The product which is precipitated towards the end of the nitration, is filtered, washed with water and re-crystallized from acetone. 

Fig. 74. Flow sheet of continuous manufacture of PETN i—nitrator No. 1, 2—nitrator No. 2. 3 — diluting vat, 4—vacuum filter, 5—washing vat, 6, 8,10,12—filters, 7—neutralizer, 9—vat for dissolving PETN in acetone, 11 —diluting...

The yield of PETN amounts 96.8%, (100 parts of pentaerythritol yield 225 parts of PETN). The raw materials required for the manufacture of 100 kg of PETN are ... 

Unphlegmatized PETN is left with a water content of 10-15%, and in this form it is transported and used for the manufacture of mixtures. 

The method outlined below for the manufacture of PETN was described by Shapshal and Belenkii [48]. 

At the Maizuru plant, in Japan [49] PETN was manufactured in World War II in a plant comprising a nitrator lined with acid-resistant steel and provided with a stirrer (140 r.p.m.), a tank made from acid-resistant steel, a centrifuge, a steel crystallizer and unit for recovering acetone. 

CIOS XXV-6 Report, Manufacture of Phlegmatized PETN, G.m.b.H. zur Ververtung Che-mischer Erzeugnisse, Wolfratshausen. 

Continuous Process for Manufacturing PETN. The following process, using stainless steel equipment, was developed during WWII at the Troisdorf Plant of Dynamit AG ... 

Secondary explosives, or high explosives, are generally less sensitive to heat and shock than primary explosives and are therefore safer to manufacture, transport, and handle. Most secondary explosives will simply burn rather than explode when ignited in air, and most can be detonated only by the nearby explosion of a primary initiator. Among the most common secondary explosives are nitroglycerin, trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and RDX. 

Biazzi Continuous Method for Manufacturing TNT German Continuous Method for Manufacturing PETN Bofors Continuous Method for Manufacturing TNT... 

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