Make Purified Chloroplatinic Acid

We process the products of dissolving platinum in aqua regia to make chloroplatinic acid.

First we reacted 31.1g of platinum with aqua regia as seen here: http://www.youtube.com/watch?v=APxL87X92t4

That solution contains unreacted nitric acid so we must destroy that. To do this we first reduce volume of the platinum containing solution by evaporating or boiling. Once it's down to less than 100mL and cooled to room temperature we add in 100mL of 15M hydrochloric acid. Then we boil the solution. The solution should be covered with an empty round bottom flask to prevent splashing out of the valuable platinum. As it boils the leftover nitric acid is reacted with the hydrochloric acid to produce nitrogen dioxide, nitrosyl chloride and chlorine gases. A yellow orange or brown gas coming from the solution indicates the reaction is occurring. We keep boiling until the solution is back down to 100mL and then allow to cool. If the gases were observed then another 100mL of hydrochloric acid should be added again and the boiling down repeated. This process should be performed as often as necessary until no gases are observed.

Once all the traces of nitric acid are destroyed the solution is reduced down to ~ 50mL and allowed to dry. Since chloroplatinic acid is extremely hygroscopic I recommend using a desiccator bag or a vacuum desiccator to dry it.

Eventually it will crystallize to an orange solid. Break it up and store it in air-tight containers away from light.

You now have purified chloroplatinic acid hexahydrate.

Видео Make Purified Chloroplatinic Acid канала NurdRage