Oxalic Acid Uses

Oxalic acid is a chemical that can be a dangerous in high doses but not in moderate levels. It is a naturally occurring component of plants such as rhubarb and buckwheat, and it is usually found in somewhat high levels in dark green leafy foods, though not high enough to cause harm to those ingesting it. Oxalic acid is also put to use in a number of ways in people's daily operations, many of which involve cleaning and bleaching.

  1. Woodwork

    • Oxalic acid is best known as an agent in wood bleaching. After long periods of exposure to sun and weather, wood can turn gray. By rubbing oxalic acid on the affected wood, you can lighten its gray appearance. Furniture refinishers also use oxalic acid after stripping wood to lighten darker-stained areas before refinishing.

    Cleaning Agent

    • Oxalic acid also is a popular cleaning agent. For instance, it is used to clean and sterilize home brewing equipment used to make beer and wine. It also is used as a purifier in the pharmaceutical industry and by rock collectors to clean various minerals and related specimens. And it works well at removing hard water stains from tile and plumbing fixtures.

    Rust Remover

    • Oxalic acid can be used to remove rust stains from kitchen counter tops, plumbing pipes and even fabric. It is used in commercial rust removers to eliminate rust stains from tubs, sinks and tile, as well as from metal.

    Other Uses

    • Oxalic acid has many other uses as well. It can be used as precipitating agent in rare-earth mineral processing, as a bleaching agent in textile production and as a grinding agent in tasks such as polishing marble. Plus, it's also used in the treatment of wastewater, because oxalic acid helps remove calcium from water. It even can be used as a reducing agent for photography.

    Warning

    • When purified, oxalic acid is very corrosive and toxic. You should use latex gloves, a dust mask and eye protection at all times while using oxalic acid, and you should always mix and use it in a well-ventilated area. Do not induce vomiting if ingested; instead drink plenty of milk or water and contact a poison control center immediately.