Explosive crystallization Filtration

If crystallization is not complete, dilution of the filtrate by the ether washings will cause separation of additional crystals. These are collected separately because they are finer and less pure. Concentration of filtrates is to be avoided because severe explosions have been reported when solutions of perchloric acid in acetic add were concentrated. 

In the hood, behind the shield, the reaction mixture is then poured into 500 ml of vigorously stirred ice water. The nitroso compound begins to separate as a fine, yellow precipitate. The product is removed by filtration and washed thoroughly with about 1 liter of cold water. After pressing the crystals dry, they are air-dried for 3 hr. Finally they are dried over calcium chloride in a desiccator yield 2.4 gm (88%), m.p. 121°C (decomposes explosively). 

The acid is allowed to run into a container of 3 m3 capacity where it is neutralized with gaseous ammonia while the temperature is raised to 70°C. The cyclonite thus formed is separated on a vacuum filter, and the filtrate is cooled when about two-thirds of the ammonium nitrate crystallizes. The latter is separated in a centrifuge, and used in the preparation of explosive mixtures. The small amounts of hexamine... 

Summary TNT can be made by treating toluene with 99% nitric acid in the presence of premium-unleaded gasoline. After the reaction, the TNT is then recovered by reciystallization. The crystallized TNT is collected by filtration, washed, dried, and then purified with 70% sulfuric acid. Commercial Industrial Note Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

In a typical experiment, a solution of 4-formyl-2,2-dimethy-l//-1,5-benzodiazepine (0.036 mol) in THF (300 mL) was added in small portions to a solution of potassium permanganate (0.063 mol) in water (100 mL) over a period of 3.5 h. (Addition of solid KMn04 to neat THF could produce an explosive mixture, and should therefore be avoided) During the addition, the mixttue was allowed to warm to about 40 C. The mixture was then filtered to remove manganese dioxide and the filtrate was concentrated and extracted with diethyl ether. After drying, the extract was concentrated and the resulting product crystallized from diisopropyl ether. The overall yield was 7 g (79%). 

Osmium tetraoxide (10 g) and ethyl alcohol (200 mL) are placed in the autoclave in that order. Carbon monoxide (CP grade) (80 atm) is then added and the reaction mixture is heated at 175 °C for 7 h. When cold (< 12 h) the pressure is released (behind an explosive proof shield). The large hexagonal yellow crystals of dodecacarbonyltriosmium are separated by filtration and washed with ice-cold ethanol (3 x 10-mL portions). The product obtained is dried under vacuum for at least 3 h (20°C, 10 mmHg). The sample thus obtained is sufficiently pure for most purposes. Further purification may be carried out by recrystallization from hot benzene. Yield 9.7-10.0 g, 97-99.5%. Other minor products from this reaction are the trinuclear derivatives HOs3(CO)io(OMe) and Os3(CO)io(OMe)2. ... 

Loss control credit factors, process hazard analysis, 873-874 Love Canal incident, 891 Low-alloy steels, equipment cost, 205 Lower explosive limit (LEL), 863 Lower flammability limit (LFL), 863 L-phenylalanine production bacteria, filtering, 1014 continuous crystallizers, 1014 continuous filtration, 1014 filtering, 1014 intermediate storage, 1014 ion exchange column, 1014... 

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