Manufacture of Perchlorates

Perchlorates can be manufactured on a small scale through decomposing the chlorates by careful heating in a quartz or porcelain crucible. Thus, e. g. potassium chlorate, if heated to 450 to 510 °C will be converted into perchlorate according to the following equation  

At the same time a small amount ot chlorate is decomposed into chloride and oxygen1 

When heated, the substance first melts, then turns into a paste, and finally solidifies. At higher temperatures or when heated excessively, the perchlorate decomposes further into potassium chloride and oxygen  

For this reason the time, of heating must be watched carefully. After the reaction mass has cooled it is leached with cold water in order to separate the easily soluble potassium chloride from the sparingly soluble potassium perchlorate. Eventually the potassium perchlorate is recrystallized from a hot water solution. The described method is commercialy unimportant as one quarter of the chlorate at least is converted into worthless potassium chloride (see equation XVIII-l). 

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Existing knowledge on perchloric acid and its salts was reviewed extensively in 1960 in a monograph including the chapters Perchloric Acid Alkali Metal, Ammonium and Alkaline Earth Perchlorates Miscellaneous Perchlorates Manufacture of Perchloric Acid and Perchlorates Analytical Chemistry of Perchlorates Perchlorates in Explosives and Propellants Miscellaneous Uses of Perchlorates Safety Considerations in Handling Perchlorates [1], There is a shorter earlier review, with a detailed treatment of the potentially catastrophic acetic anhydride-acetic acid-perchloric acid system. The violently explosive properties of methyl, ethyl and lower alkyl perchlorate esters, and the likelihood of their formation in alcohol-perchloric acid systems, are stressed. The instability of diazonium perchlorates, some when damp, is discussed [2],... 

The manufacture of perchlorate explosives is similar, but due to the lower sensitiveness to impact of perchlorate explosives, some operations as e.g. mixing, may be conducted in Drais kneaders (Figs. 173-175) or even in kneaders of Werner-Pfleiderer type (Figs. 206-208). 

Perchloric Acid. Several techniques have been employed in the manufacture of perchloric acid, including thermal decomposition of chloric acid, anodic oxidation of chloric add. irradiation of chlorine dioxide solutions, electrolysis of hydrochloric acid, oxidation of hypochlorites by ozone, ion exchange, and electiodialysis of perchlorate salts. 

Sodium chlorate is used for oxidation in organic industries and for the manufacture of perchlorates. Very often it is used as a 2 per cent solution, to destroy... 

The final product generally contains 0.04 to 0.1 per cent KC103 and not more than 0.02 per cent KC1. Potassium perchlorate is used for the manufacture of explosives and in pyrotechnics as well as for the manufacture of perchloric acid. 

Schematic Flow Diagram for the Manufacture of Ammonium Perchlorate. P 147...

Potassium pentafluoroaluminate monohydrate, 2 371 Potassium perbromate, 4 335 Potassium perchlorate, 18 277 Potassium permanganate, 9 635-636 crystallographic studies on, 15 601 as a detoxicant, 15 621 decomposition of, 15 597 as an ignitable waste, 15 615 industrial-scale production of, 15 606 manufacture of, 15 601-606 for purifying carbon dioxide streams, 4 815... 

Perchlorate is the oxidation product of chlorate. It forms a variety of compounds, including ammonium perchlorate, potassium perchlorate, sodium perchlorate, and perchloric acid. Perchlorate is highly reactive in its solid state, and as ammonium perchlorate it is used as the oxidizer in solid rocket fuel. Because of its limited shelf life, it must be periodically washed out of the country s rocket and missile inventory and replaced. Large volumes of the chemical have been disposed of since the 1950s, and perchlorate has been detected in large concentrations in both groundwater and surface water. Perchlorate has also been used in the manufacture of matches, munitions, fireworks, and in analytical chemistry. 

In the manufacture of PVC plastisol propellants, the usual care is taken to assure that all ingredients meet specifications for chemical composition, dryness, and particle size. Since PVC plastisol propellants do not involve chemical reaction in their curing process, however, the presence of certain impurities in the ingredients is far less critical than with those propellant systems that are solidified by polymerization reaction. Ammonium perchlorate, the most common oxidizer, can normally be procured from the supplier with the required low moisture content. If not, it is dried immediately before use. Tray dryers or other drying means may be used, depending upon the quantity of material. Normally, some or all of the oxidizer must be ground to achieve the desired mean particle size and particle-size distribuion. High speed hammer mills have proved... 

Lists of reagents, and recipes for working solutions and reagents are provided in Tables 1.4.1 and 1.4.2, respectively. The lactate reagent is prepared as per the manufacturer s instructions. The reagent required for the deproteinisation step is a solution of perchloric acid 1 mol/1 (dilute 8.6 ml of HCL04 70% in 100 ml distilled water or 11 ml of HCL04 60% in 100 ml distilled water). That required for the neutralisation is phosphate tripotassic buffer 1 mol/1 add 5.3 g of phosphate tripotassic in 25 ml distilled water. This solution will be stable for 1 year at 25°C. 

Early in the history of these explosives the French Commission des Substances Explosives published a report on two ammonium perchlorate Cheddites.45 The manufacture of these explosives,... 

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