Iodine Business

Iodine Business

Properties and Characteristics

General Properties of Iodine

Groundwater containing natural gas is referred to as natural gas brine, and this brine contains iodine, a globally valuable element.
Iodine, a halogen, is a semi-lustrous solid at room temperature. It sublimates readily, has a distinctive odor, and produces a purple vapor at room temperature.

▲ Iodine product

Atomic number 53
Element symbol I
Atomic weight 126.9
Density 4.93g/cm³ (20℃)
Melting point 113.6℃
Boiling point 184.4℃

Global production of iodine

Japan is the world's second largest producer of iodine after Chile. Of the iodine produced in Japan, 83% is produced in Chiba prefecture, 10% in Niigata prefecture, and 7% in Miyazaki prefecture.

Iodine is a highly valuable underground resource whose production in Japan is commercially significant worldwide.

Iodine Applications

Iodine, which has long been used as a raw material in pharmaceuticals, is currently used in a wide range of fields, from industrial applications to energy development. More recent applications include use in solar-powered hydrogen generation, which is drawing attention as a next-generation energy source, and use in coal liquefaction to produce an alternative to petroleum. Iodine is also used in advanced technological fields such as in drugs administered to protect the human body from radioactive contamination and as a material for generating laser beams. Iodine also has applications in daily living, such as in pharmaceuticals like X-ray contrast agents and new antibiotics; as an automobile seat belt and tire chemical fiber reinforcing agent; and as an agricultural chemical component and film media photosensitizing agent.

Iodine Production

Iodine Production Methods

Components in natural gas brine (compared with seawater)

Iodine exists in far higher concentrations in natural gas brine compared to seawater, and it is extracted using the blow-out process to produce commercial products.

Component Content in natural gas brine [mg/L] Content in seawater [mg/L]
Chlorine 14,000 19,000
Bromine 90 65
Iodine 40 0.05
Bicarbonate ion 770 1,400
Sodium 9,070 10,600
Potassium 480 380
Ammonium 150 -
Magnesium 480 1,270
Calcium 310 400
Iron 6 1

▲ External view of BO (blow-out) tower

Iodine production by blow-out process

  • 1: Aeration/filtration process: Impurities that hinder iodine production are removed.
  • 2: Blow-out process: Iodine vapor is expelled from the natural gas brine into the air.
  • 3: Absorption process: The iodine vapor discharged from the blow-out tower is recovered and concentrated.
  • 4: Crystallization/purification process: The purity of the recovered iodine is increased to produce the final iodine product.




Chemical formula I2
Molecular weight 253.81
CAS No. 7553-56-2
Package Fiber drum, 50 kg
Purity ≥99.7%

Potassium Iodide


Chemical formula KI
Molecular weight 166.01
CAS No. 7681-11-0
Package Cardboard box, 25 kg
Purity ≥99.5%