What Does Oxalic Acid Mean?
Oxalic acid is an organic toxic compound with the chemical formula H2C2O4. It belongs to the family of carboxylic acids. It is a
colorless crystalline solid that forms a colorless solution in
Oxalic acid is widely used for bleaching and removing rusts and stains. When removing rusts, it converts most
insoluble iron compounds into a soluble complex ion. Oxalic acid is
the prime constituent of many commercial preparations used to remove scale from automobile radiators.
Oxalic acid is also known as ethanedioic acid.
Corrosionpedia Explains Oxalic Acid
acid is an organic compound containing carboxylic acids. It is more
acidic than acetic acid. The conjugate base of oxalic acid is
oxalate (C2O42-), which is used as a chelating agent for
metal cations. Oxalic acid
is the most popular electrolytic etching solution to reveal the microstructure of austenitic stainless steels. This
is done by an oxalic acid etch
Besides bleaching and rust and stain removal, oxalic acid
is used as a reducing agent to develop photographic films. It
is also used in wastewater treatment to effectively remove calcium.
Oxalic acid in its pure
form is very toxic and corrosive. Corrosion
rates of metals in oxalic acid with other acids are different. For
rates of iron in oxalic acid are generally much less than those in
nitric acid. The corrosion rate triples in the same solutions if the
temperature is increased to 50 °C (122 °F).
Oxalic acid (OA)
is a good corrosion inhibitor for carbon steel, exhibiting good
inhibition efficiency (IE) with OA solutions with a pH greater than 3.0,
whereas for pH solutions less than 3.0, the corrosion rate is increased.