Oxalic Acid has a chemical formula of H2C2O4. Oxalic Acid appears naturally in many foods including spinach, broccoli, Brussel sprouts, grapefruit, chives and rhubarb, among many others. Oxalic Acid is an organic compound and appears as a white crystalline powder. It is about 3,000 times stronger than Acetic Acid. Its conjugate base is known as Oxalate which is a reducing agent.
Oxalic Acid is mainly used for cleaning or bleaching, especially for the removal of rust. More than a quarter of produced Oxalic Acid is used as a substance to help set dyes on fabrics, known as a 'mordant'. The word 'mordant' comes from the Latin 'mordere' which means 'to bite' as the use of Oxalic Acid helped the dye to 'bite' onto the fabric. Oxalic Acid is also used as an important reagent in lanthanide chemistry.
Diluted Oxalic Acid can be used for a range of household cleaning projects. For example, a dilute solution of Oxalic Acid can be used in the restoration of old wood to gently lighten wood tones darkened by age or finish. It can also remove black water spots from wood and remove tannin stains. A dilute solution of Oxalic Acid can be used to clean and sterilise home-brewing equipment. It can also be used by rock collectors to gently clean mineral specimens. A dilute solution of Oxalic Acid gently removes food and rust stains from kitchen worktops and sinks. Oxalic Acid solution also removes ink stains from fabrics.
Oxalic Acid is stable but sensitive to moisture so should be kept in a tightly sealed container at all times. Oxalic Acid is classified as Harmful if swallowed, inhaled or absorbed through the skin. It is corrosive and may cause burns. It is very destructive of mucous membranes and may cause burns on contact with the eyes. As when handling any chemical material care should be taken by those working with Oxalic Acid. Always read the Material Safety Data Sheet (MSDS) before using Oxalic Acid and wear appropriate Personal Protective Equipment (PPE) including overalls, safety footwear, protective gloves and approved safety spectacles.
If you have any concerns about the use or handling of Oxalic Acid contact your approved Oxalic Acid supplier who will be pleased to give advice.