Transform Your Formulations with High-Purity Citrate Ingredients

Citric acid (2-hydroxy-1,2,3-propane-tricarboxylic acid, CAS 77-92-2) is a weak acid naturally present in plants and animals. It comes in two crystalline forms: anhydrous citric acid (C6H8O7) and monohydrated citric acid (C6H8O7·H2O). Highly soluble in water and many organic solvents like ethanol, 2-propanol, ether, ethyl acetate, 1,4-dioxane, tetrahydrofuran, acetonitrile, and ethanol-water mixtures, it dissolves better in alcohol than in water, with alcohol addition greatly boosting solubility. Solubility order in various solvents is: tetrahydrofuran < 1,4-dioxane < water < 2-propanol < ethanol < acetonitrile. Citric acid can chelate metal ions by bonding through its carboxyl and hydroxyl groups, forming complexes with metals like copper, nickel, iron, magnesium, zinc, and tin, helping maintain chemical stability and prevent precipitation or property changes. As a triprotic compound, it undergoes three dissociations, enabling the formation of three types of salts and giving it buffering abilities. It forms crystalline mono-, di-, and tri-basic salts with different cations, notably calcium citrate (CAS 5785-44-4), potassium citrate (CAS 6100-05-6), magnesium citrate (CAS 153531-96-5), ferric citrate (CAS 2338-05-8), copper citrate (CAS 866-82-0), manganese citrate (CAS 2828433-42-5), and sodium citrate (CAS 86-04-2). In biochemistry, it’s essential in the metabolism of almost all living things through the Krebs cycle (also called the citric acid or tricarboxylic acid cycle), part of the energy conversion process in animals. Found naturally in citrus fruits like lemons, it’s also classified as an alpha hydroxy acid (AHA) with three carboxylic acid groups. Its salts and esters are safely used in products like printing inks, cosmetics, perfumes, and lacquers. Citric acid can also form polyesters with polyalcohols such as sorbitol and mannitol.