99.6% High Purity Oxalic Acid Crystal for Metal cleaning

Key attributes

Chemical formula: C₂H₂O₄·2H₂O

CAS: 6153-56-6

Purity: 99.6%

Production standard

COA need meets GB/T1626-2008:

References: Riel Chemical Lab1&2, National public service platform for standards information.

Introduction

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.

Physicochemical property

Our manufacturing process

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 + O 2 → 2 (CO 2 R) 2 + 2 H 2 O
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.

Application

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.

Is oxalic acid corrosive to metals

1.The influence of oxalic acid on different metals
(1) Metals prone to corrosion (Use oxalic acid with caution)
Iron, carbon steel, common steel

Oxalic acid can react with iron to form soluble ferrous oxalate, causing surface corrosion. Especially in a humid environment, it may accelerate rusting.

Short-term low concentration (such as below 5%) can be used for rust removal (converting the rust layer into iron oxalate), but it needs to be rinsed and dried in time; otherwise, it may aggravate the corrosion.

Aluminium and aluminium alloys

Oxalic acid can corrode the surface of aluminium, forming a porous oxide layer, which leads to loss of gloss or pitting.

If it is necessary to clean aluminium materials, it is recommended to use a low concentration (≤3%) and strictly control the time (< 5 minutes).

(2) Relatively corrosion-resistant metals (still with caution)
Stainless steel (304/316) :

Short-term exposure to dilute oxalic acid (such as 3% to 10%) is usually safe, but long-term immersion or high temperature may damage the passivation film and cause local corrosion.

It is recommended to rinse with clean water and dry after cleaning.

Copper and copper alloys

Oxalic acid will react with copper to form green copper oxalate. The surface may darken, but the corrosion rate is relatively slow. It can be used for polishing copperware (in combination with grinding).

(3) Metals resistant to oxalic acid
Titanium, nickel, chromium

These metals have relatively high stability in oxalic acid and are usually not easily corroded (for example, titanium can be used in oxalic acid production equipment).

2. Safety usage suggestions
Control concentration: 3% to 10% oxalic acid solution is commonly used in industrial cleaning. A high concentration (> 10%) significantly increases the risk of corrosion.

Shorten contact time: Rinse immediately with plenty of water after cleaning to avoid residue.

Adding corrosion inhibitors: such as hexamethylenetetramine (urotropine), can reduce the corrosion of metals.

Protective measures:

When operating, wear acid-resistant gloves and goggles and carry out the operation in a well-ventilated environment.

Avoid contact with skin (oxalic acid is toxic and irritating).

FAQ

1.What is your payment term?

We can accept T/T and L/C at sight as payment term.

2.Are you able to deliver on time?

Of course! we specialised in this line for many years,

many customer make a deal with me because we can deliver the goods on time and keep the goods top quality!

3.Do you provide free sample?

Yes, we can provide free sample . You only need to take the express fee.

4.How about the price?Can you make it cheaper?

We always take the customer’s benefit as the top priority.

Price is negotiable under different conditions, we are assuring you to get the most competitive price.

5.Can I visit your company and factory in China?

Sure. You are very welcomed to visit our company in Weifang, China.

(We will have someone responsible for picking up and dropping off at Weifang Airport)

6.What if there is a quality problem?

We have a professional and perfect after-sales service team, timely for you to deal with all problems.