Potassium hydrogencarbonate
[CAS# 298-14-6]

Identification

• Classification: API >> Water, electrolyte and acid-base balance regulator >> Acid-base balance regulator
• Name: Potassium hydrogencarbonate
• Synonyms: Potassium Bicarbonate
• Molecular Formula: KHCO₃
• Molecular Weight: 100.11
• CAS Registry Number: 298-14-6
• EC Number: 206-059-0
• SMILES: C(=O)(O)[O-].[K+]

Properties

• Density: 2.17 g/mL (Expl.)
• Melting point: 100 ºC (decomp.) (Expl.)
• Water solubility: 22.4% (20 ºC) (Expl.)

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H302-H315-H319-H335
• Precautionary Statements: P261-P280-P305+P351+P338

Discovory and Applicatios

Potassium hydrogencarbonate, commonly known as potassium bicarbonate, is a chemical compound with the formula KHCO₃. It is an alkali metal bicarbonate and is frequently used in a variety of industrial and laboratory applications. Potassium bicarbonate is similar to sodium bicarbonate (baking soda) but is based on potassium, a highly reactive alkali metal. This compound has a range of uses, from agriculture and food production to its role in fire extinguishers, as well as in the formulation of various chemical products. The discovery of potassium hydrogencarbonate is linked to early work on alkaline salts, and its applications have expanded over the years as the compound was found to be highly useful in different industries.

The history of potassium bicarbonate dates back to the early studies of alkali metal salts, which were extensively explored in the 18th and 19th centuries. The compound was first synthesized in the laboratory during the period of rapid advancements in chemistry, as scientists began to better understand the interactions between metals and acids. Potassium bicarbonate is produced through the reaction of potassium carbonate (K₂CO₃) with carbon dioxide (CO₂) and water (H₂O). The reaction produces potassium bicarbonate as a white, crystalline solid, which is soluble in water and has a mild alkaline nature. Since its discovery, potassium bicarbonate has been used in various applications, and its availability has grown as its usefulness became more apparent.

One of the most important applications of potassium bicarbonate is in the agricultural industry, where it is used as a fungicide. It is particularly effective in treating fungal diseases in plants, including powdery mildew, a common affliction of crops such as grapes, tomatoes, and cucumbers. Potassium bicarbonate works by altering the pH on the surface of plant leaves, making the environment less favorable for the growth of fungal spores. Unlike many other fungicides, potassium bicarbonate is considered to be relatively safe for humans, animals, and beneficial insects, making it an attractive option for organic farming and integrated pest management programs. It also acts as a natural plant fertilizer, providing potassium to plants, which is an essential nutrient for their growth and development.

In the food industry, potassium bicarbonate is used as a leavening agent in baking, where it serves as an alternative to sodium bicarbonate (baking soda). It is often used in products where sodium content must be minimized, such as in low-sodium breads or other baked goods. The leavening action of potassium bicarbonate occurs when it reacts with acids in the dough or batter, producing carbon dioxide gas that helps the dough rise. This reaction is similar to that of sodium bicarbonate, but potassium bicarbonate imparts potassium ions to the food, which can be beneficial for individuals on potassium-enriched diets. Potassium bicarbonate is also used in the production of some types of beer, as it helps control the pH level during the brewing process.

In addition to its use in agriculture and food production, potassium bicarbonate is employed in fire extinguishers, particularly in the form of dry chemical fire suppression systems. Potassium bicarbonate is effective in combating Class B and Class C fires, which involve flammable liquids and electrical equipment. When released from a fire extinguisher, potassium bicarbonate rapidly breaks down into potassium carbonate and carbon dioxide, which helps to smother the flames by depriving the fire of oxygen. Potassium bicarbonate-based fire extinguishers are often used in industrial settings, including airports, refineries, and chemical plants, where the risk of flammable liquid fires is high.

Potassium bicarbonate is also used in the production of various chemicals. It can be used as a precursor for the synthesis of potassium carbonate, potassium hydroxide, and other potassium-based compounds, which are important in industries such as glass manufacturing, soap production, and water treatment. Potassium bicarbonate is also utilized in laboratories for certain analytical procedures and as a reagent in chemical reactions.

Despite its many uses, potassium bicarbonate must be handled with care, particularly in industrial and laboratory settings. While it is generally considered safe for use in food and agriculture, excessive exposure to large quantities of potassium bicarbonate can cause irritation to the skin, eyes, and respiratory system. As with other alkaline compounds, it is important to follow safety protocols when handling potassium bicarbonate to prevent potential health hazards.

In conclusion, potassium hydrogencarbonate, or potassium bicarbonate, is a versatile chemical compound with a wide range of applications in industries such as agriculture, food production, fire safety, and chemical manufacturing. Its discovery and development have enabled its widespread use in areas ranging from plant disease control to leavening agents in baked goods. As a safe and effective substance, potassium bicarbonate continues to be an important component in various industrial and consumer products.

References

2009. Potassium Bicarbonate Attenuates the Urinary Nitrogen Excretion That Accompanies an Increase in Dietary Protein and May Promote Calcium Absorption, _The Journal of Clinical Endocrinology and Metabolism_, 94(2)
DOI: https://doi.org/10.1210/jc.2008-1796

2012, A flow injection analyser conductometric coupled system for the field analysis of free dissolved CO2 and total dissolved inorganic carbon in natural waters, _Analytical and Bioanalytical Chemistry_, 402(7)
DOI: https://doi.org/10.1007/s00216-012-5762-8

2005, Chloride-Dominant Salt Sensitivity in the Stroke-Prone Spontaneously Hypertensive Rat, _Hypertension_, 45(5)
DOI: https://doi.org/10.1161/01.hyp.0000164628.46415.66