Iron and the Environment

Iron and the Environment The natural geological iron cycle comprises weathering of rocks and subsequent water-mediated re-sedimentation. The amount of mined iron exceeds the natural circulation by an estimated factor of 8. Approximately 25% of iron production is estimated to be destroyed by corrosion and dispersed into the environment. Additional iron is emitted by combustion of iron-containing coal, but approximately 70% of scrap is returned into the steel production process. The re-utilization of scrap requires 60% less energy than smelting ores. Zinc from coated steel scrap vaporizes during crude steel production and is recovered in dust filters (Ullmann 1989). 

Iron ores Soils Ground water Drinking water Ocean water 20-70% 0.7-4.7% 0.5-100 mg L 0.3 mg 0.01-0.14 mg kg  

Meat Blood sausages Fish Dairy products 10-23 mg kg 88 mg kg 4-13 mg kg 1.2-3 mg kg-i 

Lentils Cereal products Vegetables Fruits 72 mg kg 14-28 mgkg 3-6 mg kg 2-4 mg kg  

Particulate iron and colloidal electro active Fe(III) in lake water forms small amorphous, porous balls of 0.5 tm diameter they consist of about 50% Fe(II), (Buffle et al. 1988), 50% Fe(III) and some 

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The Mossbauer effect is sensitive to the oxidation and spin state of iron and the environment around the iron nucleus therefore different chemical species yield different Mossbauer spectra. Furthermore all spin states and oxidation states of iron are accessible to the technique. There are three main components of a Mossbauer spectrum. The isomer shift arises from the electron density at the 57Fe nucleus the quadrupole splitting results from the electric field gradient produced by electrons and ions around the 57Fe nucleus, and the nuclear Zeeman splitting is sensitive to the spin state and magnetic coupling of the iron. 

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