Zinc precipitation refining is an increasingly popular form of refining metals, especially in the jewelry industry. It is a simple, environmentally friendly, and cost-effective process.
Zinc precipitation refining is commonly used to remove gold and silver from ores, concentrates, and bullion. This process takes place in a wet environment, as a chemical reaction between zinc, gold, and silver, and does not require intense heat or toxic chemicals.
The process involves adding zinc powder or zinc shavings to the solution of metals to be refined. The dissolved gold and silver will react with the zinc and form zinc sulfide, which is insoluble in the solution. As the zinc precipitates from the solution, it carries the gold and silver with it in a solid form.
Once the zinc has been removed from the solution, the metals can be readily recovered. The zinc sulfide can be separated from the gold and silver using a filter press. The filter press separates the metals by pressing the zinc sulfide slurry through a fine filter cloth. The filter press is adjustable, allowing the user to control the size of the particles that pass through the cloth and the amount of metals that are collected. The zinc sulfide is then discarded while the metals are collected and can be further refined.
The amount of metals recovered is highly dependent on the concentration of gold and silver in the solution to begin with. Generally, the more concentrated the solution, the higher the recovery rate will be.
The resulting metals are usually in the form of a fine powder. The powder can be further processed or melted to form beads, ingots, coins, or even jewelry.
Overall, zinc precipitation refining is an efficient, cost-effective, and safe method for refining gold and silver. It does not require intense heat or toxic chemicals, making it a good option for jewelry shops and hobbyists. Additionally, the results from this process are easy to analyze, enabling producers to know exactly what metals they are refining and the amount of metals they are collecting.
