Recommend 6153 56 6 99.6% Oxalic Acid For Industrial Equipment Cleaning

• Chemical formula: C₂H₂O₄*2H₂O
• CAS: 6153-56-6
• Purity: 99.6%

Oxalic acid is an organic acid with the systematic name ethanedioic acid and chemical formula HO−C(=O)−C(=O)−OH, also written as (COOH)2 or (CO2H)2 or H2C2O4. It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water.

Its name is derived from early investigators who isolated oxalic acid from flowering plants of the genus Oxalis, commonly known as wood-sorrels. It occurs naturally in many foods. Excessive ingestion of oxalic acid or prolonged skin contact can be dangerous.

• Molecular weight: 126.07 g/mol
• Appearance: White transparent crystal or powder (industrial products may be slightly yellow due to impurities)
• Odor: Tasteless or slightly sour
• Density: 1.65 g/cm³ (20°C)
• Melting point: The dihydrate loses crystalline water at 101-102°C, converting to anhydrous oxalic acid (H₂C₂O₄)
• Solubility: Water soluble (about 10 g/100 mL at 20°C), higher solubility in hot water; slightly soluble in ethanol (approx. 5.7g/100 mL at 20°C)
• Acidity: Binary acid, stronger than acetic acid (pKa₁=1.25, pKa₂=4.14)
• Reducibility: Under acidic conditions can be oxidized by strong oxidants (such as potassium permanganate)
• Complexation: Oxalate (C₂O₄²⁻) forms soluble complexes with metal ions (e.g. Fe³+, Al³+)

Oxalic acid is produced primarily by oxidizing carbohydrates or glucose with nitric acid or air in the presence of vanadium pentoxide. Another method is to regenerate nitric acid using oxygen, using a variety of precursors, including glycolic acid and glycol. As of 2011, only the Japanese company Mitsubishi has used this process.

A newer method requires oxidative carbonylation of alcohols to obtain dioxalate: 4 ROH + 4 CO + O₂ → 2 (CO₂R)₂ + 2 H₂O. These diesters are then hydrolyzed to oxalic acid. About 120,000 tons are produced annually.

Historically, oxalic acid was prepared by applying a caustic base (such as sodium hydroxide or potassium hydroxide) to sawdust and then acidifying the oxalate with an inorganic acid (such as sulfuric acid). Oxalic acid can also be formed by heating sodium formate in the presence of an alkaline catalyst.

The main uses of oxalic acid include cleaning or bleaching, especially for rust removal (iron complexing agent). Its use in rust remover is due to the fact that it forms a stable water-soluble salt with trivalent iron, namely the iron oxalate ion.

Oxalic acid is an ingredient in some teeth whitening products. About 25% of oxalic acid is used as a mordant in the dyeing process. It is also used in bleach, especially for pulping wood, cork, straw, rattan, feathers, as well as for rust removal and other cleaning, for baking powder, and as a third reagent in silica analysis instruments.

• Protective measures: Wear rubber gloves, goggles and masks; Keep the air circulating and avoid inhaling dust or steam.
• Concentration control: For household use, dilute to 3%-10% (e.g., 10g oxalic acid mixed with 100ml water). For industrial use, adjust as needed.
• Neutralization treatment: After use, rinse residue with baking soda water (alkaline) to reduce corrosion risk.

Recommended uses: Metal rust removal, cleaning of stubborn stains on tiles; Textile mordant (professional operation required).

Avoid using: Aluminium products, marble countertops, leather; Soaking clothes directly (may cause fiber damage).

• Skin contact: Rinse immediately with plenty of water for 15 minutes and seek medical attention.
• Ingestion: Do not induce vomiting. Dilute with milk or water and seek medical attention immediately.