The TOC-1000e is an online analyzer that measures the electrical conductivity (total ions) and the TOC (total organic carbon) to closely monitor the production and quality of ultrapure water. In a first step, the electrical conductivity of the water is measured, then a part of the water is oxidized by UV irradiation. This produces carbon dioxide from the organic compounds, which dissolves in the water, forming hydrogen carbonate ions and increases the electrical conductivity. The increase in electrical conductivity is a measure of the amount of organic components contained.
The device is the first system of its type to oxidize with a mercury-free excimer lamp that contains an internal glass tube through which the sample is passed for oxidation. Xenon is electrically excited so that xenon molecules are created for a short time which decay and emit UV light at a wavelength of 172nm. This UV radiation is also more energetic than the UV radiation of conventional mercury lamps.