What is potassium chlorate?
potassium salt of chloric acid (one of the four oxygen-containing acids formed chlorine: hypochlorous - HClO, chlorous - HClO2, chloric - HClO3 and bleach - HClO4) called potassium chlorate, its formula - KClO3.This salt appearance represents crystals (colorless), which are poorly soluble in water (at 20 ° C in 100 cm3 of water, 7.3 g of total dissolved salts), but with increasing temperature the solubility increases.Another of her famous name - bertoletova salt.The molecular weight substances is 122.55 atomic mass units, density - 2.32 g / cm3.The salt melts at 356 ° C, it decomposes at about 400 ° C.
opening of potassium chlorate
the first time (in 1786) of potassium chlorate was French chemist Claude Berthollet.He missed a concentrated chlorine through a hot solution of potassium hydroxide.Reaction equation, which was obtained by salt, as follows: 3Cl2 + 6KOH → 5KCl + KClO3 + 3H2O.In this reaction, potassium chlorate precipitates as a white solid.Since it is poorly soluble in cold water, it is easily separated from the other salts in the solution is cooled.Since its opening bertoletova salt is the most common and useful product of all the chlorate.Currently KClO3 produced on an industrial scale.
chemical properties
potassium chlorate salt - a strong oxidizing agent.At its interaction with concentrated hydrochloric acid (HCl) is allocated free chlorine.This process is described by the equation of chemical reaction: 6HCl + KClO3 → 3Cl ↑ + KCl + 3 H2O.Like all chlorates, a substance highly toxic.The molten form KClO3 vigorously supports combustion.In mixtures with substances easily oxidized (reducing agents) such as sulfur, phosphorus, sugar and other organic substances, potassium chlorate explodes by impact or friction.Sensitivity to these effects is enhanced in the presence of ammonium salts and bromates.Under gentle (heating to 60 ° C) the oxidation of potassium chlorate with oxalic acid to chlorine dioxide is obtained, the process proceeds according to the reaction equation: 2KClO3 + H2C2O4 → K2CO3 + CO2 + H2O + 2ClO2.Chlorine oxide finds use in the bleaching and sterilization of various materials (paper pulp flour and so on), and can also be used for wastewater obesfenolivaniya chemical plants.
application of potassium chlorate
Of bertoletova chlorate salt is the most widely used.It is used in the manufacture of dyes, matches (do combustible match head, raw material is moistened with potassium chlorate TU 6-18-24-84), fireworks, disinfectants, chlorine dioxide.Due to the high risk of potassium chlorate formulations are practically used in the manufacture of explosives for industrial and military purposes.Very rarely potassium chlorate is used as the initiating explosive.Sometimes used in pyrotechnics to yield tsvetnoplamennye compositions.Previously, the salt used in medicine: the weak solutions of the substance (KClO3) for some time been used as an antiseptic for external gargling.Salt in the early 20th century, was used to obtain oxygen in laboratory conditions, but because of the danger of the experiments were terminated.
Getting potassium chlorate
one of the following ways: chlorination potassium hydroxide as a result of the exchange reaction of chlorate with other salts, electrochemical oxidation of aqueous solutions of metal chlorides - can be obtained bertoletova salt.Preparation of its industrial scale often performed by a disproportionation reaction hypochlorite (hypochlorous acid salts).Technological processes make out differently.Most often it is based on the reaction between the calcium chlorate and potassium chloride: Ca (ClO3) 2 + 2KCl → 2KClO3 + CaCl2.Then bertoletova salt formed from the mother liquor was isolated by crystallization.Also potassium chlorate was prepared by a modified method Berthollet by electrolysis of potassium chloride: chlorine produced by electrolysis is reacted with potassium hydroxide, potassium hypochlorite resulting KClO disproportionates then KClO3 potassium chlorate and potassium chloride KCl source.
decomposition of potassium chlorate
At a temperature of about 400 ° C the decomposition of potassium chlorate.As a result, oxygen and potassium perchlorate: 4KClO3 → KCl + 3KClO4.The next stage of decomposition occurs at a temperature of 550 to 620 ° C: KClO4 ↑ + 2O2 → KCl.On catalysts (they may be copper oxide CuO, an iron oxide (III) oxide Fe2O3 or manganese (IV) MnO2) decomposition occurs at lower temperatures (150 to 300 ° C) and in one step: 2KClO3 → 2KCl + 3O2.
Safety
Berthollet salt is unstable explosive chemical that can explode with stirring, storage (for example, next to the reducing agents on the same shelf in the laboratory or in a storage room), grinding or other operations.The explosion may occur injury or even death to follow.Therefore, upon receipt, use, storage or transport of potassium chlorate must comply with the requirements of the Federal Law 116. Facilities that organized these processes relate to the hazardous production facilities.
