Sodium and Potassium Permanganate
Permanganate (MnO4) is a strong oxidizing agent that was originally discovered in 1659. As an oxidizing agent it has the ability to add oxygen, remove hydrogen or remove electrons from an element or compound. The molecular weight of permanganate is 103 g/mol. Permanganate is recognized by its characteristic pink to purple color when made into a solution.
Permanganates have been successful in the reduction of chlorinated solvents in a wide array of field implementations. A benefit of a permanganate remediation approach is the complete oxidation of the contaminant without the formation of intermediate compounds commonly found with biodegradation. For example, the breakdown of common organic solvents with sodium (NaMnO4) and potassium (KmnO4) permanganate is as follows:
4NaMnO4 + 3C2Cl4 + 4H2O > 6CO2 + 4MnO2 + 4Na+ + 12Cl- + 8H+
4KMnO4 + 3C2Cl4 + 4H2O > 6CO2 + 4MnO2 + 4K+ + 12Cl- + 8H+
2NaMnO4 + C2HCl3 > 2MnO2 + 2Na+ + 3Cl- + H+
2KMnO4 + C2HCl3 > 2MnO2 + 2K+ + 3Cl- + H+
8NaMnO4 + 3C2H2Cl2 > 6CO2 + 8MnO2 + 8Na+ + 6Cl- + 2OH- + 2H2O
8KMnO4 + 3C2H2Cl2 > 6CO2 + 8MnO2 + 8K+ + 6Cl- + 2OH- + 2H2O
10NaMnO4 + 3C2H3Cl > 6CO2 + 10MnO2 + 10Na+ + 3Cl- + 7OH- + H2O
10KMnO4 + 3C2H3Cl > 6CO2 + 10MnO2 + 10K+ + 3Cl- + 7OH- + H2O
Sodium permanganate is an inorganic oxidant that performs chemically the same way as potassium permanganate, only in a more concentrated form. The significant advantage to sodium permanganate is its high solubility in water, allowing it to be a more convenient and concentrated form of permanganate when used for organic oxidation of contaminants.