Manganese (Mn) Fraction Analysis

1. Total Mn: Analyze raw water or system water samples for total Manganese.

2. Soluble Mn: Analyze water samples using the PAN Method, but delete the use of the ascorbic acid reagent (reducing agent) in the Hach Step #6 to identify the initial soluble Mn. This portion of Mn (soluble/unbound) can be sequestered (tied-up) by adding polyphosphate into the raw water. Soluble Mn can also be oxidized and filtered out, so as to minimize potential Mn color in the system.

3. Oxidized Mn: Oxidized Mn (or organically bound Mn) can be calculated by subtracting the soluble Mn from the total Mn, (#1 – #2) = #3 (Oxidized Mn). This portion of Mn can be filtered or removed from raw water, before it escapes into the system or suspended when treated with polyphosphates to minimize color. If it precipitates in the system it must be flushed out through fire hydrants. Untreated, this Mn will slough off the pipes and create black particles and color in the water.