"Organic iron" refers to a form of iron found in water that is often more accurately described as "organically bound iron." This type of iron is formed when clear water iron in solution encounters and binds with decayed organic matter within a water supply system.
Understanding Organically Bound Iron
While commonly called "organic iron," the term "organically bound iron" provides a more precise understanding of its nature. It highlights that the iron itself is not "organic" in the biological sense but rather chemically associated with organic compounds.
According to available information, the presence of organically bound iron is attributed to a specific set of conditions:
- Clear Water Iron in Solution: This refers to iron that is dissolved in water, typically in its ferrous (Fe²⁺) state, making the water appear clear initially.
- Decayed Organic Matter: This involves the decomposition products of vegetable or animal matter present in the water supply. Sources can include decaying leaves, wood, algae, or other biological debris.
When these two components—dissolved iron and decayed organic matter—come into contact within the water supply, the iron forms a complex with the organic substances. This binding changes the properties of the iron, making it behave differently than other forms of iron, such as particulate iron or simple dissolved iron.
Key Characteristics and Formation
The formation of organically bound iron is a chemical process where dissolved iron ions interact with the humic and fulvic acids, or other organic compounds, released during the decay of organic materials.
- Cause: Clear water iron in solution entering an area of the water supply that is heavy with decayed vegetable or animal matter.
- Result: Iron becomes complexed or "bound" to the organic molecules.
- Implications: This form of iron can sometimes be more challenging to remove through conventional water treatment methods compared to other iron forms, as it often remains dissolved and may not readily settle or filter out.
