Nitration kettle

Sulfonation and nitration kettle with steam jacket (double wall). . 191... 

Nitration kettle widi auger-type stirrer, equipped far... 

Fig. 8. Nitration kettle with auger-type stirrer, equipped for external and internal cooling (1) water inlet tube for internal cooling (2) heating and cooling jacket.

The second method of disposing of the completed nitration mixture consists in cooling the products while stiU in the nitrating kettle, and thus forcing out the TNT from its acid solution. This procedure, of course, results in more dissolved TNT in the spent acid, but the time saved in the separation is very great, since the crystallization in pans requires about four days, while the nitrator separation requires but a few minutes. The nitrator separation is used especially in plants where the spent acid goes into the next charge of... 

The various compounds of sodium are the result of the ignition (in ashing) upon the impmre salts used in washing. The iron and silicon no doubt result from the action of the acid upon the nitrating kettle, which is usually of a high silicon cast iron. 

A simple jacketed pan or kettle is very commonly used in the processing industries as a reaction vessel. In many cases, such as in nitration or sulphonation reactions, heat has to be removed or added to the mixture in order either to control the rate of reaction or to bring it to completion. The addition or removal of heat is conveniently arranged by passing steam or water through a jacket fitted to the outside of the vessel or through a helical coil fitted inside the vessel. In either case some form of agitator is used to obtain even distribution in the vessel. This may be of the anchor type for very thick pastes or a propeller or turbine if the contents are not too viscous. 

Preparation of 67/33 Baratol. The approx wt of Ba nitrate, preheated to ca 90°, is added to molten TNT contained in a melting kettle equipped with an agitator. Mixing is continued until a uniform mass is obtained. Then the melt is cooled slightly while the agitation is continued and is loaded into ammo at the lowest temp at which it will flow freeIy(Ref 4)... 

Buck s Explosive, An expl compn obtained by blending two mixts previously prepd in separate kettles. Mixt 1 was prepd by fusing together 50 parts PA 50p DNPh to which was later added 4p collodion cotton. Mixt 2 was obtained by blending at 130° 50p Ba nitrate with 4-5p paraffin. 

Nitrobenzene (melting point 5.9°C, boiling point 210.9°C, density 1.199, flash point 88°C) is made by the direct nitration of benzene using a nitric acid-sulfuric acid mixture (Fig.l), usually in a cast-iron or steel kettle. 

Figures 8 and 9 show a m tration kettle with inner cooling, such as is used for nitrating aromatic hydrocarbons, and a separating funnel equipped with a hard lead or ceramic stopcock and having a window (lunette). The apparatus used for nitrating benzene must be completely lead lined because the spent acid is highly diluted at the end of the nitration and attacks iron.

The first step in the manufacture of TNT is the the nitration. This reaction is carried out in a large vessel called the nitrator. This nitrator is generally a cylindrical kettle or tank, built of either an acid-proof cast metal or of boiler plate. The material of which the nitrator is built should be thoroughly tested with the acids of various concentrations met with in the manufacture of the product. The nitrator must be well equipped with cooling coils and heating coils so placed that the temperature of the reacting mixture... 

The method used in Picatinny Arsenal [2] is as follows. The reaction was carried out in a 10-litre stainless steel kettle with a stirrer. The reagents were 2.0 I of filtered 2N silver nitrate solution, 2.01 of filtered 2N sodium azide solution, 1.07 1 of filtered pure ammonia (28%) solution. Silver nitrate followed by ammonia was introduced into the reaction kettle. Under vigorous mixing sodium azide solution was introduced and the content was warmed to 75 C within 5 min. Silver azide started to precipitate ca, 5 min later. 

Typically, stock solutions of the lead salt (acetate or nitrate) are prepared and filtered to remove grit and lead carbonate. The required quantity of stock solution is then transferred to a calibrated hold tank from whence it can be fed to the reaction kettle in a separate room. Similarly, the other reactant, sodium azide, is prepared as a stock solution, filtered, and apportioned to another hold tank. It is good practice to segregate the lead salt and the sodium azide areas from each other as well as from the reaction-kettle room. 

The five azide batches were prepared in accordance with the procedure [10], except that the solutions were added at a constant rate with metering pumps. Preparation was carried out by remote control using a stainless-steel kettle of 10-liter capacity described earlier (Figure 7). Simultaneous addition of 800 ml each of the sodium azide and lead nitrate solutions onto the surface of the reaction mixture was controlled by adjustment of the metering pumps to deliver 800 ml of solution in 20 min for batch 1, 25 min for batch 2, and 30 min for each of the other three batches. All preparations were carried out at 60°C using an agitator speed of 275 rpm. 

The laboratory method was scaled up to the minimum amount that could be successfully processed in a 10-hter stainless-steel kettle (Figure 2). fitted with a 12-cm propeller-type agitator and a 2.5-cm-wide baffle. The reactants were 2.00 liters of filtered 2 N (340 g/liters) silver nitrate solution, 2.00 liters of filtered 2N (130 g/liters) sodium azide solution, 1.07 liters of filtered reagent-grade (28%) ammonium hydroxide. 

The silver nitrate solution was transferred to the kettle, followed immedi-... 

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