Uses of Oxalic Acid

Oxalic acid is also known as an ethanedioic acid, and it is a type of dicarboxylic acid. It is a compound found naturally in many plants and vegetables. When it is in solid-state, it is odorless, colorless. But after purification, it takes the form of white crystal substance.

Also, oxalic acid is produced in the human body by the metabolism of glyoxylic acid or ascorbic acid. It is removed from the body by urine. However, this acid is used industrially as a general reducing agent. Also, it is further corrosive in nature and has a higher level of toxicity than other substances. It is essential to dispose of this chemical properly after usage.

Oxalic acid is also known as ethanedioic acid.


Oxalic Acid Uses

There are numerous counts of oxalic acid use. Talking about some of the Oxalic acid uses; basically, this chemical is an essential household product that is mainly used as a cleaner for various things. We can also look at some of the applications of this oxalic acid in any case on the below given oxalic acid uses.

  • Cleaning Agent

  • Industrial Uses

  • Medicinal uses

  • Other Uses


  • Cleaning Agent

As mentioned above, oxalic acid is mainly used for the toughest cleaning duties. The acid features such as a bleach-like quality and can be used for things similar to oxalic acid rust remover and stains on the metals and objects. This oxalic acid is found in some quantity in several cleaning products, bleaches, and detergents. Oxalic acid uses are also ideal for polishing any stone practically and treating old wood.

  • Industrial Uses

The oxalic acid is applied mostly for mineral processing mechanisms in industries. In addition, a few Oxalic acid uses can be to sterilize types of equipment, and people in the textile space use it for cloth bleaching.

  • Medicinal Uses of Oxalic Acid

The companies of the medical field make the most of this acid to further purify certain chemicals or to dilute them. However, there is a very fewer amount of data on the health benefits of this acid. Oxalic acid in raw and organic form is non-lethal. But sometimes it can cause harmful effects on the body as well.

  • Other Uses

Also, this chemical is used in addition to the chemical for bleaching, removing the stain, Oxalic acid is used mostly as a reducing element in developing photographic film. Also, it is used in wastewater treatment where this chemical removes calcium deposits from water effectively. The oxalic acid rust removal is a process to remove the rust on the products like iron.


What Acid is Used to Remove Rust?

To remove the rust for the products like iron, some strong acids will be helpful on that.

Strong alkalis and strong acids can remove rust quickly. However, these caustic chemicals pose various safety and health risks and require that the user observe strict safety precautions. Strong acids will dissolve rust, but these strong acids will also dissolve paint, finishes, and sometimes even the metal itself. Hydrochloric acid (which is otherwise known as muriatic acid when it is in diluted form), also phosphoric acid, sulfuric acid can be used as a rust removal formula using these strong acids. These strong acids are mineral acids, and especially in concentrated forms, they are highly corrosive. Strong alkalis work in the same way, but on the opposite end of the pH spectrum.

Strong acids work by dissolving rust. Most of the acid-based rust removal products are of gel formulations. If that gel remains on the metal too long after the gel is applied, it starts dissolving it, causing pitting. While on the other side, mineral acids clean away the outer layer of rust, and also they put the underlying metal in a reactive state, making it susceptible to "flash rusting," except it is otherwise neutralized or sealed.


Oxalic Acid Application

There are many oxalic acid applications that we can take from various sources. Up to 25% of oxalic acid produced will be used as a mordant in dyeing processes. It is used as a bleach, especially for pulpwood. Also, it is used in baking powder and as the third reagent in silica analysis instruments.

The oxalic acid application or the uses of oxalic acid in daily life are given below.

  • Cleaning

Oxalic acid application mainly includes bleaching or cleaning, especially the oxalic acid as a rust remover (an iron complexing agent). Its utility in rust removal agents is because of its forming a stable, water-soluble salt with ferrioxalate ion and ferric iron.


Extractive Metallurgy

Oxalic acid is a primary reagent in lanthanide chemistry. Hydrated lanthanide oxalates readily form in very strongly acidic solutions in easily filtered form, a densely crystalline, and as a largely free of contamination by non-lanthanide elements. This oxalate thermal decomposition gives the oxides, a most commonly marketed form of these elements.

  • Niche Uses

  • Oxalic acid is also used by a few beekeepers as a miticide against the parasitic varroa mite

  • This acid is used to clean minerals.

  • Oxalic acid is also sometimes used in the aluminum anodizing process, with or without sulfuric acid. Compared to the sulfuric acid anodizing, the coatings obtained are thinner and exhibit a lower surface roughness.

FAQ (Frequently Asked Questions)

1. Are Strong Acids Safe for Removing Rust?

Even when the mineral acids are diluted in water or any other substances, they are dangerous to work with, and they can damage the skin severely, irritate the lungs, and can cause other health problems without the proper safety precautions. These chemicals are toxic and corrosive, so they must be disposed of safely, especially considering large amounts.

Industrial rust removal products having strong acids can be ideal for serious rust problems, which must be quickly resolved. However, these kinds of products must be carefully monitored, and the safety precautions are to followed carefully. Precautions like proper ventilation, gloves, safety goggles, and careful application are essential to keep the users protected.

2. Mention Some Oxalic Acid Uses in Food?

There are a number of oxalic acids uses in food. Lists of foods that are high in oxalic acid vary greatly from source to source. According to the University of British Columbia, the body is well known to absorb oxalic acid only from a handful of foods, including pecans, wheat bran, peanuts, spinach, rhubarb, beet greens, beets, and chocolates. While other foods are considered as high oxalic acid ones, none of the studies shown that the body readily absorbs their oxalate content. Such include sweet potatoes, soy foods, black tea, berries, and other dark leafy greens, like Collards and Swiss chard. 

According to the article published in 2007 in the journal "Urologic Nursing," registered dietitian Laura R. Flagg has concluded as the data on oxalate foods causing kidney stones actually is "insufficient" and discouraged the limiting of these kinds of foods for patients with stones.