If I have a solution of gold chloride, is there a was I can grow metalic gold crystals to recover the gold instead of using sulfer dioxide to drop the gold as poeder?
I don't think so. Au is quite insoluble in water so it isn't possible to crystallize it from solution. You might grow crystals of AuCl3 or some other gold salt but not Au itself. With some experimentation you may find a way to reduce gold in the salt to larger pieces of gold. You might also look into plating the gold out of solution by electrolysis. When one thinks of electrolysis one usually thinks of electroplating nice layers of the metal onto a substrate; often, however, it doesn't happen that way. Often one gets, instead, crystals plating out. That might be worth a try.
Yes, it is possible to grow metallic gold crystals from a solution of gold chloride. This process is known as "electroplating" or "electrochemical deposition." Electroplating involves using an electric current to reduce gold ions in solution onto a conductive surface, resulting in the formation of metallic gold crystals.
To perform electroplating and grow gold crystals, you will need the following supplies:
1. Gold chloride solution: Prepare a solution by dissolving gold chloride in water. The concentration and purity of the solution will determine the quality of the resulting gold crystals.
2. Electrolyte: An electrolyte is needed to enhance the conductivity of the solution. Common electrolytes used for gold electroplating include sulfuric acid or gold chloride.
3. Electroplating apparatus: This includes a power supply (rectifier), two electrodes (an anode and a cathode), and a container to hold the solution.
Here's a step-by-step guide to performing electroplating to grow gold crystals:
1. Set up the electroplating apparatus: Connect the power supply to the anode and cathode electrodes. Ensure that the electrodes are submerged in the gold chloride solution but not in contact with each other.
2. Clean and prepare the cathode: The cathode will be the surface onto which the gold crystals will form. It should be clean, smooth, and made of a conductive material like copper or stainless steel. Remove any contaminants from the cathode by cleaning it with a suitable solution (e.g., dilute sulfuric acid) and rinsing with deionized water.
3. Control the electroplating conditions: Adjust the voltage and current supplied to the electrodes according to the desired deposition rate and crystal growth. Typical parameters range from 1-10 volts and 1-10 amps per square inch of surface area.
4. Begin the electroplating process: Turn on the power supply and allow the electroplating process to proceed for a specific period of time. The gold ions from the gold chloride solution will be reduced and deposited onto the cathode surface, resulting in the growth of metallic gold crystals.
5. Monitor the progress: Observe the formation of gold crystals during the electroplating process. The size, shape, and quality of the crystals will depend on factors such as deposition time, current density, and solution concentration.
6. Stop the electroplating process: Once the desired thickness or appearance of the gold crystals is achieved, turn off the power supply and remove the cathode from the solution.
7. Rinse and dry the gold crystals: Carefully rinse the gold crystals with deionized water to remove any residual electrolyte or impurities. After rinsing, gently air-dry the crystals or use a drying technique suitable for delicate metallic objects.
Remember that electroplating gold crystals requires careful handling and adherence to safety precautions, such as working in a well-ventilated area and wearing appropriate personal protective equipment.
It's worth noting that electroplating is an advanced technique, and it may require practice and experimentation to achieve the desired results.