🔥Melt your scrap metal using a melt dish and zero the scale for accurate measurements.
💎Silver chloride can form and prevent aqua regia from dissolving gold, so it's important to coat the gold with silver before using aqua regia.
🧪Use hydrochloric acid, sulfuric acid, and nitric acid to dissolve impurities and extract pure gold.
🌬️Boil the solution to remove excess fumes and evaporate excess acids.
🔬Precipitate the gold using stump out and filter to separate it from the solution.
What is Aqua Regia?
—Aqua regia is a mixture of hydrochloric acid and nitric acid, commonly used to dissolve gold and other noble metals.
Why is it important to coat the gold with silver before using aqua regia?
—Coating the gold with silver helps prevent the formation of silver chloride, which can inhibit the dissolution of gold in aqua regia.
What is the purpose of boiling the solution?
—Boiling the solution helps remove excess fumes and evaporates excess acids, resulting in a more concentrated solution.
What is stump out and why is it used?
—Stump out is sodium metabisulfite, used to precipitate gold from solution. It helps separate the gold from the impurities.
Why is it important to filter the solution?
—Filtering the solution helps separate the solid gold precipitate from the liquid solution, allowing for further purification and processing.
00:08Learn how to extract pure gold from scrap metal using aqua regia.
08:10Melt the scrap metal using a melt dish and zero the scale for accurate measurements.
17:08Boil the scrap metal in hydrochloric acid to burn off impurities.
21:28Filter the solution to remove solid impurities.
25:18Precipitate the pure gold using stump out.
26:19Melt the gold into an ingot and weigh the final yield.
