Technical Center Manager, Sybron Chemicals Inc., Birmingham, New Jersey
Pages: 7 Published: Jan 1991
The term “pure water” has a constantly changing meaning. Over the years ion exchange has played an important role in these changes. The first large scale production of 18- megohm-cm water became possible through the use of the mixed bed ion exchange process. In a sense, this was the start of pure and ultrapure waters.
Ion exchange processes will continue to play an important role in the evolution of new water grades. Ion chromatography has shown the way to measure concentrations of dissolved substances in the part per trillion (ppt) range, and new plant specifications are being measured at the ppt level, and this will result in future environmental standards.
In the future ion exchange technology will continue to lead the way, resulting in materials and processes which will accomplish the new requirements. Ion exchange resins, having low leachables, are being developed so that total organic carbon (TOC) levels can be achieved in pure water. Selective ion exchange materials with chelating functionality are appearing. These, coupled with stable conventional ion exchange resin, will help to solve waste problems resulting from toxic and radioactive substances.
ion exchange, semiconductor industry, pure water, total organic carbon, leachables, bacterial contamination
Paper ID: STP17607S