Precious metals mainly refers to gold, silver and platinum group metals (
Ruthenium, rhodium, palladium, osmium, iridium, platinum,
Eight kinds of metallic elements.
Most of these metals have beautiful colour and lustre, resistance to chemicals is quite big, not easy to cause chemical reaction under general conditions.
Containing precious metal material is divided into two kinds: one kind is mineral resources, known as a resource;
Another kind is renewable resources, it is in use process scrap precious metal products, such as different kinds of resources, forms, from the very few to almost pure metal, called secondary resources.
Precious metals smelting technology has obvious progress in recent years, effective extraction of the precious metals can be divided into: the enrichment of -
Refining of three parts.
From solution containing metal composition more refined to extract precious metals usually adopt solvent extraction technology of industrial application.
Over the years in such aspects as extractive separation technology and equipment are constantly innovation and development, the existing precious metals extraction plant is unable to slow speed of extraction, extraction, extraction of poor quality, extraction equipment also develops from the traditional mixer settler. cwl - of modern times
M new centrifugal extraction machine.
The equipment and energy saving effect is good, low power consumption, and on the corrosion resistance for the corrosive system, adopts the polymer composite materials instead of the traditional metal materials, to solve the corrosion problem of the equipment.
Adopted on the stability of hanging structure, cancelled the equipment at the bottom of the bearing and mechanical seal, simplifies the equipment structure, from the source to solve the traditional centrifugal extraction machine easy leakage, mechanical failure is frequent, the problem of short service life.
Equipment adopts a variety of mixed structure, separation effect is good, the characteristics of small amount of the liquid.
Due to the process operation continuity is strong, high automatic degree and the cycle is shorten, recovery rate and the higher the purity of the product, get a lot of technical and economic benefits, has become one of the major equipment and separation of precious metals, refining method.
the traditional process of precious metals gold platinum palladium smelting is repeatedly melt crystallization and repeated restore purified.
New extraction technology for gold platinum palladium extraction, gold platinum palladium with aqueous chlorination process first platinum palladium first gold melt first, after dissolving or with reduction of sulfur dioxide in sodium sulfate reduction control reduction potential (
Improve the potential control mol degrees)
Make gold reduction, a coarse gold, to gold, the rest of the liquid inside is platinum, palladium, zinc, bismuth and other metal, the metal with the method of ammonium, adding ammonium chloride, the palladium into the liquid inside, the platinum in the solid phase, there's just a rough separation of platinum and palladium.
After reoccupy chloride aqueous solution, melting into the liquid, palladium with target extraction, extraction after loaded organic phase with hydrochloric acid with pure water again after washing impurity or sodium hydroxide reverse extraction, the extraction of palladium extraction residue were adjusted with platinum N235 extraction, the extraction agent high extraction rate of platinum (
To the base metals such as copper iron nickel and cobalt extraction rate, innovative technology, good continuity, to adapt to the range.
A platinum liquid over extraction with p204 extraction base metals, platinum and palladium after gold rhodium iridium solution after extracting, do chemical precipitation with ammonium chloride, burns into platinum powder melting into platinum ingot.
precious metals solution of metal ions by extraction and its valence configuration and the nature of solution, a lot of the extraction mechanism and the results show that the extraction process of chlorine in the solution with anionic valence state controlled by the central ions and solution properties, and its changes in extraction behavior of major change.