Potassium permanganate is an antiseptic and antimicrobial first aid agent for disinfecting wounds, mucous membranes and gastric lavage, so it is advisable to have it in your home medicine cabinet. Many people believe that dry matter has an unlimited shelf life. But is this really so? How and for how long you can store potassium permanganate in dry and liquid form, read on.
General characteristics
The chemical formula of potassium permanganate is KMnO4. In other words, it is the potassium salt of permanganate acid (potassium permanganate).
This crystalline substance has a dark violet (almost black) color. It dissolves well in water, giving it a bright crimson color.
Potassium permanganate is also used for household needs (dying, washing, disinfecting, etc. of various objects and surfaces).
The product is sold in dry form. In this case, crystalline powder is often packaged in small glass containers. Less often - in special paper-based bags.
In past times, a ready-made 5% solution of potassium permanganate was sold. But today it is prohibited for sale.
Even taking into account the many advantages of this substance, it cannot be called safe for health. Its improper use can lead to serious consequences.
How long does potassium permanganate last?
Potassium permanganate has an official name - potassium permanganate. According to the chemical composition, it is a potassium salt of manganese acid (KMnO4). The crystals are colored dark purple, almost black with a steely sheen; the solution ranges from light pink to dark crimson, depending on the concentration.
Potassium permanganate is a chemical used in medicine, therefore, in accordance with the legislation of the Russian Federation, a shelf life and expiration date are established for it.
- Shelf life is the period of time during which, subject to all manufacturer requirements, the drug retains the qualities and properties declared during production.
- Shelf life is the period of time after which the product becomes unsuitable for use. It can be indicated as a date (best before) or as a time period (best within) (Article 472 of the Civil Code of the Russian Federation).
Read more about the shelf life and storage of medications in a separate article.
If, after the established storage period, the quality indicators of the drug have not changed, then it is suitable for use until the expiration date.
The countdown of any duration of a medicinal product begins from the date of its production. This period of time includes:
- the presence of the drug in the manufacturer’s warehouse;
- transportation to the place of storage or sale;
- stay in the warehouses of retail outlets.
Shelf life
The guaranteed shelf life of potassium permanganate for medical purposes according to GOST 20491 - 75 is 3 years. The substance intended for agricultural needs and other industries is stored for up to 1 year (GOST 57774 - 84).
The manufacturer's packaging usually indicates the expiration date of potassium permanganate in crystals or powder. According to the manufacturer, it is 5 years for use for medicinal purposes. Longer storage reduces the quality of the substance, as a result of which it partially loses its antiseptic properties, while becoming insoluble.
The shelf life of potassium permanganate solution (5%) is only 2 days from the moment of preparation. In this case, the specific time for which diluted potassium permanganate can be stored depends on its concentration and external temperature.
You can store the product in the form of a dry powder for the same amount of time as crystals.
Storage conditions
How to store potassium permanganate at home? The substance (in any state) should be kept dry and cool , away from light . An open flame is especially dangerous for it.
Temperature values for successful storage should be in the range - +10°C - +20°C (but not higher than +25°C!).
Children should not reach the container with potassium permanganate. If the concentrate of this substance gets on the skin or mucous membrane, burns will inevitably form.
A temperature of +240°C promotes the decomposition of potassium permanganate with the release of large amounts of oxygen.
When potassium permanganate interacts with oils, glycerin-containing products, phosphorus, sulfur, it can ignite and even cause an explosive reaction, so you should not store them nearby.
The best storage container is a glass jar with a tight-fitting lid. It is put away on a separate shelf in a dark, dry pantry.
Reagent storage groups, methodological development in chemistry on the topic
Reagent storage groups
| Group number | General properties of substances in this group | Examples of substances | Storage conditions at school |
| I | Explosives. | Not included in the “Model Lists” | It is prohibited to bring into the school building |
| II | Releases flammable gases when interacting with water | Lithium, sodium, calcium, magnesium metal; calcium carbide | In the laboratory, in a locked cabinet or together with the flammable liquid |
| III | Spontaneously ignite in air if not stored properly | Not included in the “Model Lists” | |
| IV | Flammable liquids (flammable liquids) | Diethyl ether, acetone, benzene, ethyl alcohol, toluene, cyclohexane, isobutyl alcohol, benzene, aminoacetic acid, crude oil, formalin 40% etc. | In a laboratory room in a metal box or in a special factory container |
| V | Flammable solids | Cutting sulfur, red phosphorus, benzoic acid, palmitic acid, oleic acid, stearic acid, activated carbon, graphite, paraffin, dry fuel | In the laboratory, in the closet under lock and key |
| VI | Flammable (oxidizing) reagents | Potassium permanganate, nitric acid, potassium sodium nitrates, manganese (IV) oxide, hydrogen peroxide, aluminum nitrate, ammonium nitrate | In the laboratory, in the closet, separate from IV and V groups |
| VII | Increased physiological activity | Bromine, ammonia, barium oxide, potassium hydroxide, sodium hydroxide, calcium oxide, calcium hydroxide, lead(II) oxide, ammonium dichromate, barium nitrate, aniline | In the laboratory in the safe |
| VIII | Low hazardous substances and practically safe | Sodium chloride, sucrose, chalk, boric acid, magnesium sulfate… | In the classroom in locked cabinets or in the laboratory in cabinets |
Information about the special properties and storage groups of substances
For all substances the following characteristics are given below:
- Special note (column 2). If there is an * sign here, then in the forms provided for by the “Model Lists” the substance is used only by the teacher. Students can be given substances in the form of diluted solutions.
If a ** sign is placed in this column, then the substance requires special handling due to the fact that it has high physiological activity in relatively small doses, an increased fire hazard, or possible severe long-term consequences of exposure to the body. Not issued to students in original forms.
If there is no special mark, then the substance, subject to safety regulations, is used by everyone without restrictions.
2. Groups of storage of substances are determined primarily by their chemical compatibility: in case of accidental displacement of substances of the same group, there should be no interaction between them or, if this occurs, the reaction products and thermal effect should not pose a danger (Column 3).
3. The effect on the body is indicated in column 4. If the substance is not
poses a danger either for short-term or long-term
influence, a dash is placed in the column.
4. The “+” sign next to the name indicates substances that penetrate into
the body in a droplet-liquid state through the skin.
| Substance name | Special mark | Storage group | The effect of substances on the body |
| Simple substances | |||
| Aluminum metal (granules) | VIII | — | |
| Bromine in ampoules of 5 g | ** | VII | Chemical burn |
| Reduced iron (powder) | VIII | — | |
| Crystalline iodine | ** | VII | Chemical burn |
| Calcium metal | * | II | Chemical burn |
| Silicon metal | VIII | — | |
| Lithium metal | * | II | Chemical burn |
| Magnesium metal | * | II | — |
| Sodium metal | * | II | Chemical burn |
| Sulfur | V | Eczema in particularly sensitive people | |
| Phosphorus red | * | V | Skin diseases of various types |
| Zinc metal (granules) | VIII | — | |
| Zinc (dust) | * | VIII | — |
| Oxides, hydroxides | |||
| Aluminum hydroxide | VIII | Irritation of mucous membranes by dust | |
| Aluminum oxide is harmless | VIII | ||
| Ammonia 25% | VII | upper respiratory tract catarrh | |
| Barium oxide | ** | VII | Poisoning if ingested |
| Barium hydroxide | ** | VII | |
| Iron(III) hydroxide | VIII | — | |
| Iron(III) oxide | VIII | — | |
| Potassium hydroxide (granules) | ** | VII | Ulceration of the skin of the fingers, destruction of nails. Particularly dangerous if it gets in the eyes. |
| Calcium oxide | ** | VII | |
| Calcium hydroxide | ** | VII | |
| Magnesium oxide | VIII | — | |
| Manganese (IV) oxide (powder) | VI | — | |
| Copper hydroxide | * | VIII | Severe irritation, especially in areas of microtrauma. Mild allergies. |
| Copper(II) oxide (powder) | * | VIII | |
| Copper (II) oxide (granules) | * | VIII | |
| Caustic soda (granules) | ** | VII | Ulceration of the skin of the fingers, destruction of nails. Particularly dangerous if it gets in the eyes. |
| Hydrogen peroxide | * | VI | Burn of mucous membranes upon ingestion |
| Phosphorus(V) oxide | * | VII | Irritation on contact with wet skin |
| Zinc oxide | VIII | — | |
| Salts | |||
| Aluminum chloride | VIII | Irritation of mucous membranes by dust | |
| Aluminum sulfate | VIII | ||
| Potassium alum | VIII | ||
| Aluminum nitrate | ** | VI | Carcinogen, like all nitrates |
| Ammonium carbonate | VIII | — | |
| Ammonium nitrate | ** | VI | Carcinogen |
| Ammonium chloride | VIII | — | |
| Ammonium dichromate | ** | VII | Skin ulceration, poisoning if ingested (lethal dose - 1 g or more) |
| Ammonium thiocyanate | * | VIII | — |
| Ammonium sulfate | VIII | — | |
| Barium nitrate | ** | VII | Poisoning if ingested |
| Barium chloride | ** | VII | |
| Iron(III) chloride | * | VIII | — |
| Iron (III) sulfate | VIII | — | |
| Iron (III) sulfate heptahydrate | VIII | — | |
| Potassium acetate | VIII | — | |
| Potassium bromide | ** | VIII | — |
| Potassium bicarbonate | VIII | — | |
| Potassium hydrogen sulfate | VIII | — | |
| Potassium dichromate | ** | VII | Skin ulceration, poisoning if ingested (lethal dose - 1 g or more) |
| Potassium iodide | ** | VIII | — |
| Potassium carbonate | VIII | — | |
| Potassium monohydrogen phosphate | VIII | — | |
| Potassium nitrate | ** | VI | Carcinogen |
| Potassium permanganate | ** | VI | Poisoning if ingested (lethal dose - 1 g or more) |
| Potassium thiocyanate | * | VII | Narcotic effect when taken orally (acute psychosis, dose 30g) |
| Potassium sulfate | VIII | — | |
| Potassium ferro(II) hexacyanide | ** | VII | Poisoning by cyanide, which can be formed during decomposition under the influence of gastric juice |
| Potassium ferro(III)hexacyanide | ** | VII | |
| Potassium chloride | VIII | — | |
| Potassium chromate | ** | VII | Skin ulceration, poisoning if ingested (lethal dose - 1 g or more) |
| Calcium dihydrogen phosphate | VIII | — | |
| Calcium sulfate | VIII | — | |
| Calcium phosphate | VIII | — | |
| Calcium hydrogen phosphate | VIII | — | |
| Calcium chloride dihydrate | VIII | — | |
| Cobalt sulfate | * | VII | Acute dermatitis from dust-like substances, acute poisoning (from 1 g and above) |
| Lithium chloride | VIII | Skin irritation | |
| Magnesium sulfate | VIII | — | |
| Magnesium chloride | VIII | — | |
| Manganese (II) sulfate | * | VIII | Irritation of damaged skin areas, impaired healing of microtraumas |
| Manganese(II) chloride | * | VIII | |
| Copper(II) hydroxycarbonate | VIII | Severe irritation, especially in areas of microtrauma. Mild allergies. | |
| Copper (II) sulfate anhydrous | VIII | ||
| Copper (II) sulfate pentahydrate | VIII | ||
| Copper(II)chloride | VIII | ||
| Sodium acetate | VIII | — | |
| Sodium bromide | VIII | — | |
| Sodium bicarbonate | VIII | — | |
| Sodium hydrogen sulfate | VIII | — | |
| Sodium carbonate | VIII | — | |
| Sodium carbonate decahydrate | VIII | — | |
| Sodium metasilicate | VIII | Damage to the mucous membranes of the eyes from dust | |
| Sodium nitrate | ** | VI | Carcinogen |
| Sodium orthophosphate aqueous | VIII | — | |
| Sodium hydrogen phosphate | VIII | — | |
| Sodium dihydrogen orthophosphate | VIII | — | |
| Sodium sulfide ninehydrate | VII | Poisoning if ingested (lethal dose - 3-5 g or more) | |
| Sodium sulfate anhydrous | VIII | — | |
| Sodium sulfate decahydrate | VIII | — | |
| Sodium sulfite | VIII | — | |
| Sodium thiosulfate | VIII | — | |
| Sodium fluoride | ** | VII | Poisoning if ingested (lethal dose - 0.2 g or more) |
| Sodium chloride | VIII | — | |
| Nickel sulfate | * | VIII | Carcinogen |
| Lead acetate | ** | VII | Severe poisoning if ingested (dose 0.5 g for an adult; 01 g for a child) |
| Silver nitrate | ** | VII | Carcinogen |
| Chromium(III) chloride | ** | VII | Carcinogen |
| Zinc sulfate | ** | VIII | Skin irritation, gastrointestinal disorders |
| Zinc chloride | ** | VII | |
| Acids | |||
| Nitric acid (density 1.42) | VII | Chemical burn | |
| Boric acid | VIII | Chemical burn | |
| Formic acid (85%) | VII | Chemical burn | |
| Orthophosphoric acid | VIII | Chemical burn | |
| Sulfuric acid (density 1.84) | VII | Chemical burn | |
| Hydrochloric acid (density 1.19) | VII | Chemical burn | |
| Acetic acid (tech.) | VII | Chemical burn, severe irritation of the upper respiratory tract | |
| Organic matter | |||
| Aniline + | ** | VII | Poisoning by inhalation of vapors and through skin. Severe poisoning from 2-3 drops |
| Aniline sulfate | ** | VII | Less toxic than aniline |
| Acetone | IV | Narcotic effect (if inhaled in large doses) | |
| Benzaldehyde | * | IV | Severe eye irritation |
| Benzene + | ** | IV | Destruction of the liver, blood, drying of the skin |
| Hexane | IV | — | |
| Hexachlorobenzene | ** | VII | Eye irritation (even from small doses), causes increased fatigue |
| Glycerol | IV | — | |
| Glucose | VIII | — | |
| Dichloroethane | ** | VII | Generally toxic effect (lethal dose for an adult - 10-15 ml) |
| Diethyl ether | IV | Narcotic effect | |
| Aminoacetic acid | IV | — | |
| Benzoic acid | * | V | Skin irritation |
| Butyric acid + | ** | IV | Very severe skin and upper respiratory tract irritation |
| Oleic acid | V | — | |
| Palmitic acid | V | — | |
| Stearic acid | V | — | |
| Xylene + | * | IV | Destruction of the liver, blood, drying of the skin |
| Methylamine | * | VIII | Upper respiratory tract irritation |
| Crude oil | Mild skin irritation | ||
| Sucrose | VIII | — | |
| Butyl alcohol | * | IV | Skin irritation |
| Isoamyl alcohol | ** | VII | Poisonous. Causes mental disorders. Narcotic effect |
| Isobutyl alcohol | * | IV | Skin irritation |
| Ethanol | * | IV | Narcotic effect |
| Toluene + | * | IV | Somewhat less toxic than benzene |
| Carbon tetrachloride | ** | VII | Narcotic effect (causes violent state). In case of chronic poisoning, the liver suffers |
| Ethyl acetate + | * | IV | Dermatitis and eczema |
| Acetic isoamyl ester | ** | VII | Narcotic effect. Upper respiratory tract irritation |
| Phenol + | ** | VII | Severe poisoning if in contact with skin in the form of a concentrated solution |
| Formalin 40% | * | IV | Causes acute poisoning. Easily penetrates the body in any form |
| Chloroform | ** | VII | Vapors cause anesthesia, after which there is an acute disorder of the whole body |
| Methylene chloride | ** | VII | Acute poisoning from inhalation of vapors. In children, death can occur from 1-2 breaths |
| Cyclohexane | * | IV | Mild skin irritation |
| Ethylene glycol | IV | — | |
| Materials | |||
| Aluminum metal | VIII | — | |
| Activated carbon | V | — | |
| Graphite | V | — | |
| Copper metal | VIII | — | |
| Iron(III) sulfide (pyrite) | VIII | — | |
| Calcium carbonate | VIII | — | |
| Calcium carbide | ** | II | Dermatitis, long-lasting ulcers. In case of contact with eyes, loss of vision |
| Paraffin | V | — | |
| Soda lime | ** | VII | Ulceration of the skin of the fingers, destruction of nails. Particularly dangerous if it gets in the eyes. |
| Dry fuel | V | — |
How to store the solution
How and for how long can a solution of potassium permanganate be stored? In the form of a solution, the product can be stored for only 2 days. This is true if it is intended for use for medicinal purposes. At the same time, it is impossible to use metal objects when making the solution in order to avoid the onset of a chemical reaction.
Before using the solution for its intended purpose, you should make sure that there are no undissolved crystals left at the bottom of the container, which can cause burns.
Potassium permanganate solution is stored in a cool place, in a hermetically sealed glass container.
After two days, the remaining liquid is poured out. And the container is thoroughly washed without using products with glycerin and different types of oils in the composition.
