Stainless steel filters also known as Sparging Stones can be cleaned by ultra-sonication in 30% phosphoric acid; clean afterwards with DI water (ultra-sonication) and then methanol (ultra-sonication).
Same would be true for all metal filters, like inlet filters and more. But be aware, only the metal part! No PEEK rings, connectors or housings.
Step 1 Cleaning with phosphoric acid.
Step 2 Removing the acid from the filter with water.
Step 3 Conditioning the filter for hydrophobic / hydrophilic solvents with methanol.
If you know which solvent you are going to use the sparging stone with, you could condition the stones with these solvents, but be aware of their miscibility with water.
Always use powder free floves when handling sparging stones.
For customers such as in the wine industry, use of 1M NaOH can be effective in the removal of compounds such as tartrates. Just be sure to thoroughly rinse and clean the sparging stone afterwards with a lot of water or even methanol.
