Processing gold involves several key stages to separate it from other materials and refine it into a pure state.
Based on common processing methods, the gold is first separated from the cyanide solution. Following this separation, the gold is smelted to eliminate some of its impurities. The resulting molten gold, known as crude bullion, is then poured into molds to solidify. To achieve high purity, this crude bullion undergoes further refinement through specialized processes.
Steps in Gold Processing
The process outlined in the reference details the steps after initial recovery (often involving cyanide leaching):
- Separation from Cyanide Solution: After gold is dissolved using cyanide, it needs to be extracted from this solution.
- Smelting: The separated gold material is heated to a high temperature. This process melts the gold and helps remove certain impurities, resulting in a less pure form of gold.
- Casting Crude Bullion: The molten gold from smelting, referred to as crude bullion, is poured into molds. Once cooled and solidified, it forms bars or other shapes ready for the next stage.
- Further Refinement: To transform crude bullion into pure gold, additional refining steps are necessary.
Gold Refining Methods
The final stage involves refining the crude bullion to remove remaining impurities and achieve the desired purity level. According to the reference, this can be accomplished by:
- Electrolytic Refining: An electrochemical process that uses an electric current to dissolve and re-deposit gold, leaving impurities behind.
- Chlorination: A process that uses chlorine gas to convert impurities into volatile chlorides, which are then removed.
- Acid Leaching Processes: Utilizing acids to dissolve and remove specific impurities from the gold.
These methods are employed to produce highly pure gold material suitable for various applications, from investment and jewelry to electronics.
Refining Method Summary
Here's a quick look at the refining processes mentioned:
| Method | Principle | Purpose |
|---|---|---|
| Electrolytic Refining | Uses electricity to purify | High-purity gold production |
| Chlorination | Uses chlorine gas to remove impurities | Impurity removal as chlorides |
| Acid Leaching | Uses acids to dissolve and remove impurities | Specific impurity removal |
By undergoing these structured steps – from separation and smelting to casting and advanced refining – gold is processed from a recovered state into a pure, valuable commodity.
