Deuterium-depleted water

Deuterium-depleted water (DDW), also known (more ambiguously) as light water, is water which has a lower concentration of deuterium (2H) than occurs naturally on earth.[1] The deuterium atom (whether bonded or ionized) is a heavier isotope of hydrogen, having (in each atom, in addition to its single proton) a neutron that (very nearly) doubles the atomic mass of the atom compared to the vastly more common protium (1H) isotope.

Not to be confused with "light water", referring to water that is not heavy water.

In Vienna Standard Mean Ocean Water (VSMOW) that defines the isotopic composition of the ocean water, deuterium occurs at a concentration of 155.76 ppm.[2] For the SLAP (Standard Light Antarctic Precipitation) standard that determines the isotopic composition of natural water from the Antarctic, the concentration of deuterium is 89.02 ppm.[3] The production of heavy water involves isolating and removing deuterium containing isotopologue within natural water. The by-product of this process is deuterium-depleted water.

Various technologies have been developed for the production of deuterium depleted water, such as electrolysis,[4] distillation (low-temperature vacuum rectification),[5][6] desalination from seawater,[7] Girdler sulfide process,[8] and catalytic exchange.[9]

Due to the heterogeneity of hydrological conditions natural water in its isotopic composition varies around the globe. Distance from the ocean and the equator and the height above sea level have a positive correlation with water deuterium depletion.[10]

Snow water especially from glacial mountain meltwater is significantly lighter than ocean water. The weight quantities of isotopologues in natural water are calculated on the basis of the data collected using molecular spectroscopy:[11][12]

Water isotopologue Molecular mass Content, g/kg
VSMOW SLAP
1H216O 18.01056470 997.032536356 997.317982662
1H2H16O 19.01684144 0.328000097 0.187668379
2H216O 20.02311819 0.000026900 0.000008804
1H217O 19.01478127 0.411509070 0.388988825
1H2H17O 20.02105801 0.000134998 0.000072993
2H217O 21.02733476 0.000000011 0.000000003
1H218O 20.01481037 2.227063738 2.104884332
1H2H18O 21.02108711 0.000728769 0.000393984
2H218O 22.02736386 0.000000059 0.000000018

According to the table above the weight concentration of heavy isotopologues in natural water can reach 2.97 g/kg, thus, there are about 300 milligrams of deuterium containing isotopologues in each liter of water. This presents a significant value comparable, for example, with the content of mineral salts.[13]

Positive biological effects of deuterium-depleted water were registered during experiments with different species.[14][15]

See also

References
  1. PMID 23773696
  2. https://nucleus.iaea.org/rpst/Documents/tecdoc_0825.pdf International Atomic Energy Agency (1993). "Reference and Intercomparison materials for stable isotopes of light elements". Proceedings of a Consultants Meeting Held in Vienna.
  3. https://nucleus.iaea.org/rpst/documents/VSMOW_SLAP.pdf International Atomic Energy Agency (IAEA): Reference Sheet for International Measurement Standards.
  4. László Kótai, József Lippart, István Gács, Béla Kazinczy, and László Vidra. Plant-Scale Method for the Preparation of Deuterium-Depleted Water. Ind. Eng. Chem. Res. 1999, 38, 6, 2425–2427 doi:10.1021/ie9807248
  5. Stefanescu, I.; Titescu, G.; Titescu, G. M. B. Obtaining deuterium depleted potable water involves feeding purified water to isotopic distillation column in presence of packing on theoretical plates and feeding reflux flow on plate of superior stripping zone, with specific plate ratio. Patent WO2006028400-A1, 2006.
  6. Stefanescu, I.; Peculea, M.; Titescu, G. Process and plant for obtaining biologically active water depleted of deuterium - from natural water or water from heavy water manufacture. Patent RO112422-B1, 1998.
  7. Zlotopolski, V. M. Plant for producing low deuterium water from sea water. U.S. Patent 2005/0109604A1, 2005.
  8. Cong, F. S. Manufacture of deuterium-depleted water for use in pharmaceuticals, involves circulating liquid raw water between cold and heat-exchange towers, and transferring heavy constituent in cold tower to liquid phase by chemical exchange. Patent CN101117210-A, 2007.
  9. Method for the Production of Deuterium-Depleted Potable Water Feng Huang and Changgong Meng Ind. Eng. Chem. Res. 2011, 50, 378–381.
  10. https://link.springer.com/chapter/10.1007%2F978-3-642-67161-6_22 Stable Hydrogen and Oxygen Isotopes in the Water Cycle.
  11. Rothman et al., J. Quant. Spectrosc. Radiat. Transfer, 1998, 60, 665. Rothman et al., J. Quant. Spectrosc. Radiat. Transfer, 2003, 82, p.9.
  12. Patent (Russia) 2295493. "Method and installation for the production of light water." Soloviev S.P.
  13. https://www.ars.usda.gov/ARSUserFiles/80400525/Articles/NDBC32_WaterMin.pdf Pehrsson, K. Patterson, C. Perry, The Mineral Content of US Drinking and Municipal Water. USDA, Agricultural Research Service, Human Nutrition Research Center, Nutrient Data Laboratory, Beltsville, MD.
  14. GLEASON J.D., FRIEDMAN I. Oats may grow better in water depleted in oxygen 18 and deuterium. NATURE 256, 305 (24 July 1975).
  15. https://www.ncbi.nlm.nih.gov/pubmed/15984656 Bild, W; Năstasă, V; Haulică (2004). "In Vivo and in Vitro Research on the Biological Effects of Deuterium-depleted water: Influence of Deuterium-depleted water on Cultured Cell Growth". Rom J. Physiol. 41 (1–2): 53–67.
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