Extracting gold from damaged mobile phones

Extracting gold from damaged mobile phones Extracting gold from damaged mobile phones can be an interesting and potentially rewarding process, but it requires some technical expertise, the right materials, and safety precautions. The gold in mobile phones is usually found in small quantities on the connectors, circuit boards, and sometimes on the pins of chips. Here's a general guide on how to extract gold from old or damaged mobile phones: Materials You’ll Need: - Old mobile phones (damaged or discarded) - Screwdrivers (for dismantling the phone) - Tweezers - Gold-plated circuit boards or components (after dismantling the phones) - Protective gloves and safety glasses - Nitric acid - Hydrochloric acid (optional) - Plastic containers (for mixing chemicals) - A plastic tray or basin - Plastic or wooden stirrers (for handling chemicals) - Safety equipment (ventilated workspace, respirator, etc.) Step-by-Step Process for Extracting Gold: 1. Disassemble the Mobile Phones - Remove the battery: Always remove the battery first to avoid any electrical hazard. - Open the phone: Use a small screwdriver to open the mobile phone and remove all the screws. Be careful as mobile phones have delicate internal components. - Separate the parts: Remove components like the circuit board, camera, connectors, and buttons. - Identify gold components: The gold is typically found in connectors, on the motherboard, and on the SIM card slot, among other small parts. Look for gold-plated pins and connectors. 2. Collect the Gold-Plated Components - Using tweezers, carefully remove any gold-plated connectors and circuit boards. Gold is typically present in very thin layers, so don't expect large quantities. - For larger pieces, the gold might be found on connectors or pins, which can be removed using pliers. 3. Use Nitric Acid to Dissolve Base Metals - Prepare your work area: Ensure you're working in a well-ventilated area, preferably outdoors, as nitric acid can release toxic fumes. - Prepare a mixture of nitric acid and water: Dilute the nitric acid (usually in a 1:3 ratio of acid to water) in a plastic container. This will help dissolve any base metals like copper and leave behind the gold. - Place the gold-plated components in the acid: Immerse the gold-plated parts into the acid mixture. - Wait for reaction: The nitric acid will dissolve the base metals, leaving the gold behind. This process can take several hours, depending on the amount of base metals on the components. 4. Separate the Gold from the Solution - After the base metals are dissolved, you should be left with a gold residue or gold particles in the solution. - Rinse the remaining gold: Use clean water to wash the gold residue and remove any acid. 5. Use Aqua Regia (Optional) to Refine the Gold - If you wish to refine the gold further, you can use aqua regia (a mixture of hydrochloric acid and nitric acid) to dissolve the gold and purify it. This is an optional step and is more advanced. - Prepare aqua regia: Mix hydrochloric acid with nitric acid in a 3:1 ratio. Be very careful when handling this mixture, as it's highly corrosive. - Dissolve the gold: Add the gold residue into the aqua regia solution and allow it to dissolve. - After the gold is dissolved, you can extract the gold from the solution by adding a reducing agent, such as urea, to precipitate the gold. 6. Purification and Final Gold Recovery - After dissolving and separating the gold, the next step is to purify it. This is often done by precipitation (using chemicals like sodium metabisulfite) or electrolysis. - The gold will settle at the bottom as a fine gold powder or nugget, which can then be collected, rinsed, and dried. Safety Precautions: - Always wear gloves and safety glasses when handling acids or any chemicals to prevent injury. - Work in a well-ventilated area or use a fume hood, as fumes from nitric acid or aqua regia are toxic and can cause respiratory issues. - Dispose of chemicals safely: Never dispose of acids or chemicals in regular waste. Follow local regulations for proper disposal of hazardous materials. - Handle equipment carefully: Use plastic or non-reactive containers to avoid contamination or accidents. Important Notes: - The amount of gold in a single mobile phone is very small, so extracting gold from many phones is necessary to make it worthwhile. - Gold recovery from electronic waste is often done at a commercial scale by specialized companies, as it requires advanced processes and safety protocols. - This DIY method is more of a learning experience and should be undertaken with great caution.