How to measure the concentration of deuterium oxide D2O with DMA 5000 M

Deuterium oxide is a liquid solvent where hydrogen atoms in a water molecule are replaced by the heavier isotope atoms deuterium. D2O is used for example as cooling liquid in nuclear reactors, in medicinal diagnostics, in research and for NMR (Nuclear Magnetic Resonance) analyses.


Deuterium Oxide, also called "heavy water", has the chemical formula D2O. The deuterium atom, expressed by the symbol D, is a hydrogen isotope. The difference between D2O and "regular" water H2O lies in the core of the hydrogen atom: hydrogen 1H, also called protium, has only one proton, whereas deuterium D, also written as 2H, has a proton and a neutron in its nucleus. The additional neutron makes the D2O molecule, when compared to water H2O, heavier. The hydrogen isotope tritium 3H even has a second neutron in its core.

The molar mass of D2O is 20.0276 g/mol. Its density is higher than the density of H2O. D2O is used in Nuclear Magnetic Resonance (NMR) spectroscopy, in organic chemistry, Fourier Transform Infrared (FTIR) spectroscopy, and in some types of nuclear reactors as a moderator to slow down the velocity of neutrons.

Deuterium’s natural abundance is 0.015 per cent. In other words, water contains 150 ppm of deuterium. For the production of heavy water, the concentration of deuterium can be augmented by means of distillation, electrolysis or by means of the so-called Girdler sulfide process, an isotopic exchange process of hydrogen atoms between H2S and H2O over several temperature steps. The exchange of deuterium depends on the temperature. High temperatures enhance the migration to H2S, low temperatures preferably to H2O. Deuterium enriched water with a deuterium content of above 99 % can be produced. What remains is deuterium depleted water.

Get the document

To receive this document please enter your email below.