Ion Exchange Technology:Protecting the Water of Life

Research and development on ion exchange membranes began 80 years ago.
Since then, the technology has supported the lives of people through production of table salt and desalination/refining of drinking water, foods,and medical intermediates. In addition, it helps preserve the earth’s environment through applications including waste liquid processing and recovery of valuables.

The History of Developing Ion Exchange Membranes

Tokuyama was established to manufacture soda ash and calcium chloride from salt as a raw material. The Company relied on imports for industrial salt, and it was a challenge to secure a stable supply at a reasonable price. To overcome this, Tokuyama invented a patented process to produce brine by concentrating seawater with ion exchange membranes. Tokuyama began research on ion exchange membranes around 1938 and, in 1961, became the first in the world to successfully manufacture an ion exchange membrane. The technology to concentrate inorganic electrolyte solution using this membrane was highly praised by industry and academia.
Manufacturing technology for ion exchange membranes originated in the field of organic synthesis, an area where Tokuyama had little experience. After conquering many obstacles in developing the membrane, Tokuyama established a process to prepare brine using ion exchange membranes,then later commercialized it as a salt manufacturing method. The efforts of many researchers and engineers came together in the development of these membranes, which built the foundation for Tokuyama’s subsequent growth.

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Ion Exchange Technology Application Fields

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NEOSEPTA ion exchange membrane

Contributing to Safe, Healthy Living

Today, the ion exchange membrane business is carried out by the group company, ASTOM Corporation. Ion exchange membranes are utilized in processes including manufacture,waste liquid processing, and recycling of various substances by leveraging effects such as desalination, concentration,recovery, separation and refining.

A New Production Process for Table Salt: Ion Exchange Membranes

For many years table salt in Japan was made by drying salt in the sun, but since 1972 productivity has increased dramatically with the application of electrodialysis using ion exchange membranes.

Producing Safe Drinking Water from Underground Water

Ion exchange membranes are also useful in production of drinking water, which, along with salt, is essential to life. On remote islands and in other regions reliant on underground water, often salinity exceeds the standards for tap water. ASTOM supplies drinking water that fulfills tap water standards by effectively desalinating water using electrodialysis reversal.

Products and Technologies Compatible with Strict Environmental Regulations

Recovering Valuables from Plant Effluent

Ion exchange membranes are also utilized in the recovery of valuables from plant effluent.
The bipolar membrane electrodialyzer from ASTOM recovers acid and alkali from saline effluent and also achieves volume reduction. Examples include the recovery and recycling of valuables from potassium fluoride waste from semiconductor and liquid crystal plants.

Recovering Valuables from Plant Effluent

Recovering Valuables from Plant Effluent

Apparatus to Reduce the Volume of Plant Wastewater

Apparatus to Reduce the Volume of Plant Wastewater

Global Growth in China, India and Other Countries

In rapidly industrializing China and India, reducing the volume of industrial wastewater is becoming a major issue, and the demand for zero liquid discharge is growing. Particularly in China, more inland plants, including coal-chemical plants and thermal power generation plants, are adopting technologies to meet the country’s tightening effluent regulations. This includes ASTOM’s electrodialysis, which enables further concentration of wastewater and reduces the volume of concentrated wastewater. The products’ high functionality and maintenance-saving durability will help drive ASTOM's business growth and foster a recycling-oriented society.

Building an Exciting Company by Developing New Membranes Technologies

Tokio Okoshi


As a provider of electrodialysis systems using hydrocarbon-based ion exchange membranes,ASTOM is focusing our energies beyond Japan. We are moving forward with several projects such as the installation and pilot operation of test equipment for new applications on production lines in China, South Korea and Southeast Asia. We also help customers to reduce environmental impact by enabling them to cut down on and reuse plant wastewater. In addition, ASTOM aims to be a global leader in ion exchange technology by proactively developing new membranes.
Company Outline
Established: May 1,1995
Location:6-2, Nishi-shinbashi 2-chome, Minato-ku,Tokyo 105-0003, Japan
Capital:450 million yen
Shareholders:Tokuyama Corp. 55%,Asahi Kasei Corp. 45%
President:Tokio Okoshi
Main businesses:Manufacture and sale of ion exchange membranes and systems

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