Borax
Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. Powdered borax is white, consisting of soft colorless crystals that dissolve in water. A number of closely related minerals or stone compounds that differ i…
Gold Chlorination Processes & Methods
Chlorination Process for Gold. This process was based on the fact that chlorine, in the presence of moisture, converts gold into the trichloride AuCl3 , which is soluble in water and removed by washing, the gold being then precipitated by ferrous sulphate, sulphur dioxide, hydrogen sulphide, or charcoal.
Gold Chlorination Process by Miller
Gold Chlorination Process by Miller. Miller’s Gold Chlorination process was introduced by F.B. Miller. The refining process employs chlorine gas, which passed into molten gold covered with a layer of borax and silica, and reacts with most of metals present in the …
How to Leach Gold Ore With Chlorination | Sciencing
Apr 25, 2017 · Gold can be leached from stone through alkaline or acidic-based products, including halogens, such as chlorine, iodine and bromine. Halogens are reactive, non-metal elements with seven electrons in their outer shell which allow them to easily combine with other elements.
Newbery–Vautin chlorination process - Wikipedia
The process of extracting gold from ores by absorption of the precious metal in chlorine gas, from which it is reduced to a metallic state, is not a very new discovery. It was first introduced by Karl Friedrich Plattneraround 1848, and at that time promised to revolutionize the processes for gold extraction. By degrees it was found that only a very clever chemist could work this process with practically perfect results, for many reasons. Lime and magnesia might be contained in the quartz, and would be attacked by the chlorine. …
Gold processing - Refining | Britannica
Gold processing - Gold processing - Refining: Gold extracted by amalgamation or cyanidation contains a variety of impurities, including zinc, copper, silver, and iron. Two methods are commonly employed for purification: the Miller process and the Wohlwill process. The Miller process is based on the fact that virtually all the impurities present in gold combine with gaseous chlorine more ...
Processing, smelting and refining gold | World Gold Council
The Miller process uses gaseous chlorine to extract impurities when gold is at melting point; impurities separate into a layer on the surface of the molten purified gold. The Miller process is rapid and simple, but it produces gold of only about 99.5 percent purity. The Wohlwill process increases purity to about 99.99 percent by electrolysis.
Gold extraction by chlorination using a pyrometallurgical ...
The feasibility to recover the gold present in alluvial material, by means of a chlorination process, using chlorine as a reactive agent, has been studied. The influence of temperature and reaction time was studied through changes in the reactant solid.
Gold extraction by chlorination using a pyrometallurgical ...
The feasibility to recover the gold present in alluvial material, by means of a chlorination process, using chlorine as a reactive agent, has been studied. The influence of temperature and reaction time was stud-ied through changes in the reactant solid. The techniques used to …
Gold processing | Britannica
With E.B. Miller’s process of refining impure gold with chlorine gas (patented in Britain in 1867) and Emil Wohlwill’s electrorefining process (introduced in Hamburg, Ger., in 1878), it became possible routinely to achieve higher purities than had been allowed by fire refining.
Miller process - Wikipedia
This stone process involves blowing a stream of pure chlorine gas over and through a crucible filled with molten, but impure, gold. This process purifies the gold because nearly all other elements will form chlorides before gold does, and they can then be removed as salts that are insoluble in …
Gold Extraction by Chlorination Process - YouTube
Aug 23, 2014 · Modern technology has improved the process of using chlorine as a method to dissolve gold. Resin technologies have virtually eliminated the early problems associated with using chlorine …
CHLORIDE HYPOCHLORITE OXIDATION AND LEACHING OF …
Chloride–hypochlorite oxidation and leaching of refractory sulfide gold concentrate 63 Fig. 1. The Pourbaix diagram of Fe–S at [Fe] –= 10 4 M, [S] = 10– M and 25 C (the chlorine species regions are also marked) (Marsden and House, 2005) Fig. 2.
Extraction of Gold
Bromine acts more energetically than chlorine, and has also been employed in the extraction. The recovery of the gold is effected similarly, and the bromine is then liberated by the action of chlorine, but it is impossible to prevent loss of bromine. Cyanide-process The extraction of gold by the cyanide-method is of great technical importance.
Gold Extraction and Recovery Processes
process, (iii) electrowinning and (iv) ion-exchange / solvent extraction. Traditionally, Merrill-Crowe process was used to remove gold from a cyanide solution by using zinc dust to precipitate gold from its solution. Carbon adsorption is increasing using in newer plants for gold …
chlorination in processing gold ore - MC World.INC
Gold Chlorination Processes MethodsWith the exception of the Malm process, chlorine processes for raw ores of the precious metals are necessarily confined to t …
Chlorination - an overview | ScienceDirect Topics
Chlorination was the first stone water disinfection process and began to be used as a standard unit process at water treatment plants (WTPs) as early as 1902. Initially, solid chloride of lime (i.e. calcium hypochlorite) was used but was quickly replaced at larger WTPs by the more efficient chlorine gas.
Refining of Gold at the Rand Refinery - SAIMM
Chamber of Mines investigated the possibility of establishing a local gold refinery. The technical aspects were discussed with Sir T.K. Rose, a leading authority on gold metallurgy, and the chlorine refining process was chosen specifically with a view to the rapid and effective treatment of …