There are multiple ways to recover and refine the platinum in catalytic converters, but the processes vary in their simplicity and in the quality of platinum they produce. Mechanical methods are by far the easiest way to collect the platinum from catalytic converters, but they give low yields. Chemical methods provide the best yields, but they require using hazardous chemicals, expensive refining equipment and chemical expertise to work safely and effectively.
The easiest way to recover the platinum from a catalytic converter is to disassemble the converter and recover the platinum-covered ceramic balls or honeycomb from inside the part. After recovering the platinum-covered parts, remove the platinum coatings manually using a screwdriver or other sharp tool. A faster but significantly more difficult way to recover platinum mechanically is to pulverize the ceramics and then collect the platinum using fractional melting.
There are two chemical methods to refine platinum: using strong acid or carbochlorination. Using strong acid dissolves pulverized platinum and ceramics in either sulfuric or hydrochloric acid. Depending on the acid used, this forms either platinum sulphates or chlorides, which are then easy to precipitate using a simple acid-base reaction. Carbochlorination also forms platinum chlorides, but this technique use a mixture of chlorine and carbon monoxide gas to extract platinum from the ceramic mixture. Because of the extreme danger and difficulty of using chlorine and carbon monoxide gas, carbochlorination is only practical in laboratory or industrial settings.