Potassium Periodate CAS 7790-21-8

This mature process features low cost and high conversion rate, making it the preferred industrial route for producing the product. Its core principle is to oxidize iodine with chlorine to form periodic acid, which then undergoes neutralization with potassium hydroxide to yield the target product.

First, add an appropriate amount of water into a reaction kettle as the reaction medium, then feed iodine and stir to disperse it uniformly. Next, slowly introduce chlorine gas to initiate the oxidation reaction, with the temperature controlled at 40–50 ℃. Chlorine is used in excess to ensure complete oxidation of iodine to periodic acid (HIO₄), and continuous stirring is maintained during the reaction to improve mass transfer efficiency. After oxidation is completed, filter the reaction solution to remove impurities, obtaining a pure periodic acid solution.

Slowly add potassium hydroxide solution dropwise to the periodic acid solution until the pH reaches 2–3. At this point, periodic acid reacts with potassium hydroxide via neutralization to form the product, with the reaction equation:HIO₄ + KOH → KIO₄↓ + H₂O

After neutralization, evaporate and concentrate the reaction solution. Upon cooling to room temperature, potassium periodate crystals precipitate. The product is then processed by centrifugal separation, washing, and drying at 100–105 ℃ to obtain finished it with a purity of over 98%.

This method is suitable for laboratory-scale preparation, with readily available raw materials and simple operation. It uses potassium iodate and potassium persulfate as main raw materials and conducts oxidation under alkaline conditions.

Dissolve potassium iodate in 30% potassium hydroxide solution, heat to boiling, then add potassium persulfate in portions under stirring. Continue boiling for 5–10 minutes to allow the reaction to produce it and potassium sulfate.

After the reaction, cool the mixture to room temperature and filter to remove the precipitated potassium sulfate. Wash the precipitate and combine the washings with the filtrate. Neutralize the solution to neutrality with sulfuric acid to precipitate it crystals. Wash the crystals with ice water until the sulfate ion content meets the specification, then centrifuge and dry to obtain the finished product, with a yield of 80%–85%.

Chlorine is toxic and flammable; the reaction must be performed in a closed system, and tail gas must be treated by absorption before discharge.

Reaction temperature must be strictly controlled: excessively high temperature causes product decomposition, while low temperature reduces reaction rate.

It is a strong oxidizing agent. Keep it away from reducing agents and flammable materials during synthesis to avoid safety incidents. The finished product should be stored sealed in a cool and ventilated area.

KIO ₄, as an important high valent iodine compound, has wide application value in analytical chemistry, organic synthesis, and materials science. Its strong oxidizing properties and special reactivity make it an indispensable reagent in chemical research and industrial production.Its discovery can be traced back to related research after the discovery of iodine element.

In 1811, French chemist Bernard Courtois first discovered iodine during the preparation of potassium nitrate. Subsequently, scientists began to systematically study various compounds of iodine.

In 1825, German chemist Justus von Liebig first observed the presence of KIO ₄ while studying iodate, but was unable to isolate pure KIO ₄ at that time.

In 1833, French chemist Auguste Laurent successfully prepared KIO ₄ for the first time while studying the oxygen-containing acids of iodine. He obtained this compound by electrolyzing potassium iodate solution and described its properties preliminarily.

In the 1840s, with the establishment of redox theory, scientists began to understand the essence of KIO ₄ as a strong oxidant. In the mid to late 19th century, with the development of structural chemistry, the molecular structure of KIO ₄ was gradually elucidated.

In 1860, British chemist Edward Frankland determined the tetrahedral structure of the high iodate ion (IO ₄⁻) through systematic oxidation experiments. This discovery laid the foundation for understanding the chemical properties of periodate salts.

In 1872, Russian chemist Alexander Butlerov first systematically studied the thermal decomposition properties of KIO ₄ and found that it would decompose into potassium iodate and oxygen at high temperatures.

In the 1880s, Swedish chemist Svante Arrhenius used KIO ₄ as a model compound to verify its dissociation behavior in aqueous solutions while studying the theory of electrolyte solutions.