Aqua Regia

What is the aqua regia?

Aqua regia, also known as a royal water, is include mixture of hydrochloric acid and nitric acid, respectively. Aqua regia can dissolve many metals that are normally very difficult to dissolve. These metals are known as noble metals, so the solution that can dissolve them is called royal water.

During work It is necessary safety precautions. It is corrosive and may result in explosion or skin burns if not handled with extreme caution. It causes destruction of living tissue at site of contact. Corrosive effects can occur not only on the skin and eyes, also causing respiratory tract irritation.

Which metals does dissolve in aqua regia?

Aqua regia is one of the strongest acids and is capable of dissolving Au and Pt. Aqua regia can rapidly attacks gold.  Platinum is attacked by aqua regia and mixtures of hydrochloric acid and oxidizing agents.

Zirconium and Hafnium can also dissolve by aqua regia.

Which metals does not dissolve in aqua regia?

Metallic Ag does not dissolve in aqua regia.

Ruthenium is the most chemically resistant of the platinum metal sand is not attacked or dissolved by either hot or cold aqua regia. Tantalum is not attacked by aqua regia at ordinary temperatures. Niobium has been reported to have a corrosion rate of low aqua regia at 55°C.

Iridium resists cold and boiling aqua regia, but may be dissolved by Aqua regia under pressure by heating to 250 to 300 °C.

Rhodium is not attacked by aqua regia at 100 °C in either wrought or cast form.

How can storage the aqua regia?

It is not recommended to store Aqua Regia for safety reasons. During to chemical operation, the solution decomposes quickly, releasing nitrosyl chloride, nitric oxide, and chlorine. However, if the liquid is stored in a closed container (polypropylene, teflon or glass), the resulting gas buildup can cause the bottle to burst. If storage of Aqua Regia is obligatory, it should be kept in a chemical fume hood far away from flammable substances (such as organic components etc.), and in a container that allows gas to escape.

How to recover gold from aqua regia?

The aqua regia is one of the method gold recovery processes. It is preferred more because of the chemical is find easy and cheap. To prepare aqua regia we need to mix one part of nitric acid and three parts of hydrochloric acid. Especially the gold can recovery from e-waste, mining, and scrap jewelry by this way. any precautions are taken to ensure the complete recovery of gold from the aqua regia solution, and the correct choice of the gold reducing chemical is also very important part of this gold recovery process.

As Proses Makina Team,

One of these solutions, we eliminates the red fume and waste problem caused by gold refining with the chemical solutions it offers. One of these machines, the scrubber unit are aimed to wash the acid gases that will occur during chemical leaching and make them harmless in terms of environment and human health in legal emission limits. 

One of the other machines is our leach reactors made of titanium or polypropylene that can rotate around its own axis and resistant to aqua regia.

We provide physical and chemical solutions according to our customer’s demand. We are guaranteed %99,99 purity gold recovery from mining, e-waste, and scrap jewelry.

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