Metals Solubility Chart

Most dissolved metals are removed from wastewater by raising the pH so they form insoluble metal hydroxides that can be settled, floated or filtered. Each metal is least soluble at a different pH, which is why mixed-metal wastewater often needs more than one treatment step.

Redrawn from Pan America Environmental's original chart. Values are approximate and for reference only; the actual solubility in your wastewater also depends on chelating agents, temperature and other dissolved substances. Lab testing confirms the right pH and chemistry.