Gold Treatment With Sulfuric Acid

Gold treatment with sulfuric acid is the process of dissolution of metals such as zinc, iron and other metal impurities using dilute sulfuric acid (H2SO4) and of the acid treatment process will be easier to concentrate on the stage before the phase of purification of the melting process for making pure gold, because. metallic impurities such as zinc, iron and other impurities that are integrated with the content of gold ore has been dissolved by liquid sulfuric acid (H2SO4). The process of Acid Treatment on gold is very important to do before proceeding to the gold metal smelting process, due to deposition of the cementation process is carried out is still a lot of metal-containing zinc, iron and tin are also entrained. In the use of dilute sulfuric acid (H2SO4) is a blend of metal impurities will easily soluble by dilute sulfuric acid (H2SO4), is a metal that has a positive electrode potential in electrochemical series is rather difficult to dissolve, because the greater the tendency to become ions, and vice versa. A metal with a more negative potential shifts the metal underneath any of the salt solution. Sulfuric acid (sulphuric acid) is a highly corrosive strong mineral acid with the molecular formula H2SO4. The historical name of this acid is oil of vitriol. The sulfuric acid is a colorless to slightly yellow liquid which is clear or viscous and is soluble in water at all concentrations. It is a dibasic acid. The corrosiveness of it is mainly due to its strong acidic nature, strong dehydrating property and if concentrated strong oxidizing property.

SMELTING

Smelting is a form of extractive metallurgy; its main use is to the process of separating the metal from impurities by heating the concentrate to a high temperature to cause the metal to melt. Smelting the concentrate produces a metal or a high-grade metallic mixture along with a solid waste product called slag.

This includes iron extraction from iron ore, and copper extraction and other base metals from their ores. This usually involves the reduction of metal oxides (ore) to metal (reduction reaction are those which take electrons away from the elements, the reduction becomes the opposite of oxidation reactions), and the formation of non-metal oxide waste known as slag.

Smelting uses heat and a chemical reducing agent to change the oxidation state of the metal ore; the reducing agent is commonly a source of carbon such as coke, or in earlier times charcoal. The carbon or carbon monoxide derived from it removes oxygen from the ore to leave the metal. The carbon is thus oxidized in two stages, producing first carbon monoxide and then carbon dioxide.

And in the process of smelting, the ore minerals may be added by Chemical Fusing Metallic Minerals such as borax, backing soda, or with ammonium chloride (NH4Cl) to mineral-borne heavy metals along with gold ore minerals can be separated. Fluxes are used in smelting for several purposes, chief among them catalyzing the desired reactions and chemically binding to unwanted impurities or reaction products. Calcium oxide, in the form of lime, was often used for this purpose, since it could react with the carbon dioxide sulfur dioxide produced during roasting and smelting to keep them out of the working environment.

  

HERE ARE A FEW COMPOSITIONS USED IN METAL SMELTING

Aqua Regia

Aqua regia is the result of mixing a solution of hydrochloric acid (HCl) and a solution of aqua fortis or more in the know with Nitric Acid (HNO3), which is part of an oxidant the most powerful.

Aqua regia is a highly corrosive, fuming yellow or red solution.  In a mixing between Nitric Acid (HNO3) and hydrochloric acid (HCl) is 3: 1, That is the volume of a solution of 3 parts hydrochloric acid (HCl) was added to 1 volume part of the solution of Nitric Acid (HNO3) .

Aqua regia or in Latin is more known as royal water is a chemical solvent all the metals. It is one of the few reagents that dissolves as gold, platinum and palladium from substrates, particularly in microfabrications and microelectronics labs.

It was so named because it can dissolve the so-called royal, or noble metals, although tantalum, iridium, and a few other metals are able to withstand it. Glassware may also be washed with aqua regia to remove organic compounds only in trace amounts. Aqua regia solutions are extremely corrosive and may result in explosion or skin burns if not handled with extreme caution.

*  Decomposition Of Aqua Regia

Gold Precipitation Methods

Gold precipitate is precipitated in the process of refining gold metal in the form of dust or fine particles are colored a brownish, and the precipitate obtained from the reaction of the chemical separation of metallic gold with aqua regia. In decision precipitates in aqua regia solution that has been contained gold metal content is required several stages. And eventually precipitated from these precipitates can be dissolved to be made in a metallic gold.

Some stages are used to obtain precipitates gold result from the process of refining gold ore with aqua regia solution can use the following steps.

Processing Flow Chart Of Gold

Mining gold from year to year is always an increase, in which the processing system became more developed, ranging from mining system that uses a simple system to a more modern processing system. Gold mining was first carried out in alluvial areas. Processing system is also very simple to do that is by panning using a tray, which then developed with gold mining wave table, and followed by gravity separation method using the amalgamation process with the capture of mercury. Gold exploration in the lower layers of soil to get the primary sediment deposits began in 1860 with gold using a cyanide treatment system. And in 1960 the method of processing low-grade gold began being applied, which carried out the processing system through leaching heap, this process is basically developed from gold processing system using cyanidation . Of all the gold mineral processing must go through several stages in all these stages it is absolutely live to get the desired results, as for some stages it can be underlined by the diagram below

 OPEN PIT MINING