7789-20-0 Usage
Description
Deuterium oxide (D2O), also known as heavy water, is a colorless liquid in which the hydrogen atoms (1H) are replaced by the heavier isotope deuterium (2H, symbol D). It forms hexagonal crystals upon freezing and exhibits distinct physical properties compared to regular water, with a relative density of 1.105, melting point of 3.8°C, and boiling point of 101.4°C. Deuterium oxide occurs naturally in trace amounts (about 0.003% by weight) in water sources and can be separated through fractional distillation or electrolysis. It is a valuable compound in various scientific and industrial applications due to its unique properties.
Uses
Used in Chemical Research:
Deuterium oxide is used as a solvent for preparing specifically labeled isotopologs of organic compounds, which aids in studying chemical reaction rates and mechanisms.
Used in Nuclear Reactors:
In the nuclear industry, deuterium oxide is utilized as a neutron moderator in reactors due to its low cross-section for capturing thermal neutrons. This property allows it to reduce neutron energies without significantly diminishing the neutron flux, making it an essential component in certain types of nuclear reactors and tritium production.
Used in Nuclear Magnetic Resonance (NMR) Spectroscopy:
Deuterium oxide is employed as a 100% isotopically enriched NMR solvent, widely used in high-resolution NMR studies. It helps in the identification of labile hydrogens and provides valuable insights into various thermodynamic properties, such as intermolecular vibrational frequencies, energy of the hydrogen bond, free energy, enthalpy, and entropy.
Used in Fourier Transform Infrared (FTIR) Spectroscopy:
Deuterium oxide is often used as a substitute for water in the analysis of proteins in solution by using FTIR. This application allows for a more accurate assessment of protein structures and interactions.
Physical and chemical characteristics
Deuterium oxide, also known as "heavy water", "deuterium water", is the compound of oxygen and the heavy isotope of hydrogen, namely deuterium, which is the most important deuterium compound. It is called heavy water because its density is heavier than ordinary and its chemical formula is D2O.The liquid is colorless and odorless in normal temperature and pressure, containing the isotope of hydrogen with mass twice that of ordinary hydrogen. Compared to ordinary water, its chemical characteristic is relatively inactive with specific gravity of 1.10775 (25 ℃), melting point of 3.82 ℃, boiling point of 101.42 ℃. The content of heavy water in natural water is 1/5000. The ratio of deuterium to hydrogen in ordinary water is 1:6000 and the reserve of deuterium in Dead Sea or deep sea is relatively richer. There is no water origin in nature with rich deuterium. Heavy water is similar to ordinary water in appearance but with many different physical characteristics. The hydrogen bond strength and degree of association between heavy water molecules are both bigger than that of ordinary water molecules and the heavy water has higher melting point and boiling point. The vapor pressure of heavy water is smaller than that of ordinary water, which is the theoretical basis for enriching
Deuterium oxide using water distillation method. The viscosity of heavy water at 25℃ is 2.3% larger than that of ordinary water making the electrical conductivity of electrolyte in heavy water is smaller than in ordinary water and the specific inductive capacity of heavy water is smaller than ordinary water. The solubility of salts in heavy water is usually smaller and at 25 ℃ 1 g water can dissolve 0.3592 g sodium chloride while 1g heavy water can only? dissolved 0.3592g sodium chloride. The distribution coefficient at 25℃ between carbon tetrachloride and water is 85:1 while 103:1 between carbon tetrachloride and deuterium oxide. The surface tension and ionic product ([D+7][OD+]=2×10-15) of heavy water are both smaller than that of water and in the same chemical reaction deuterium oxide reacts more slowly than water. Just like the concentrated sulfuric acid, heavy water can absorb water and must be kept in sealed containers. Heavy water can be used as nuclear moderator and heat reduction lubricant in the atomic reactor.
The information above is compiled by YaoYao in lookchem.
Application history
In 1931, after finding Deuterium H C Urey also found an increase in centration of deuterium in liquid waste of electrolytic cell, proposing the idea that uses water electrolysis to enrich heavy water. In 1933 G N Louis electrolyze 10L liquid waste of electrolytic cell repeatly obtaining 0.5μL heavy water with concentration of about 65.7% and nearly pure deuterium oxide can be obtained? after electrolysising the heavy water again. Some certain physical constants are obtained with this initial droplet heavy water. The relative molecular mass of heavy water is 20.0275, 11% larger than that of ordinary water of which the relative molecular mass is18.0153 and its physical characteristic is different from ordinary water. The melting point of heavy water is 3.82℃ with boiling point 101.42℃ and density (25℃) 1.10445 g/cm3. The neutron absorption cross section of heavy water is very small (only 5.3 x 10-4 barn) as the most ideal moderator in thermal reactor. Heavy water is used as moderator in many reactors such as Savannah River production reactor built in the United States in the 1950s, the power reactor used in nuclear power plants of Canada, and the research reactors in many countries. The deuterium in heavy water is an important part of fusion power reactor fuel. And deuterium oxide is extremely important strategic material. During world warⅡ, the Allies and the Nazi Germany attached great importance to heavy water production which was kept great secret. When the Allies learned that Nazi Germany was producing heavy water in the Norilsk factory of Norway, they first sent special detachment in 1943 to attack the factory and then bomb the factory using plane, making Nazi Germany suffered a serious setback in their efforts to develop nuclear weapons. In 1943 the United States built a number of large-scale deuterium oxide plants with annual production of about 20t. In the 90s many countries in the world can produce heavy water with annual production capacity of about 2000t.China started to develop heavy water production since the 50s and export deuterium oxide in the 80s. The price of heavy water per ton in the international market price is about $230000.
References: Dedi Chen, Zhou Li, and editor Guisheng Ku. National Defense Economy Dictionary. Beijing: Military Science Press. 2001.
Main use and function
Deuterium oxide can be used as neutron moderator and heat carrier in nuclear fission reactors and can also be used in chemical and biological research. The deuterium from heavy water electrolysis is the charging of hydrogen bombs.
Heavy water is mainly used as moderator in nuclear reactor to reduce the neutron velocity and control the nuclear fission process and also as coolant. Heavy water and deuterium are valuable tracer materials in the study of chemical and physiological changes. For example, diluted heavy water can run from more than ten meters to tens of meters per hour after irrigating trees with dilute water. The heavy water molecule can stay in human body for 14 days on average after measuring the content of deuterium in the urine of human drinking a large amount of diluted water. Deuterium can be used to research the digestion and metabolism of animal and plant instead of ordinary hydrogen. Concentrated or pure heavy water can not maintain the life of animals and plants and heavy water lead animal and plant to death at the concentration of 60%.
Marine deuterium oxide
Water consisting of deuterium and oxygen is indeed heavier than ordinary water because of deuterium in molecule and is called "heavy water" (D2O) . Heavy water is a kind of huge energy source and can be used as moderator and heat transfer medium in atomic energy reactor and also raw material of hydrogen bomb. The fusion reaction of deuterium can release huge energy. There is 200 tons of heavy water in seawater and once the heavy water is extracted the world's oceans can provide human beings with inexhaustible energy.
Now the method of producing heavy water in large scale including? distillation, electrolysis, chemical exchange, adsorption and so on. Distillation based on the difference of vapor pressure of light water(H2O), semi-heavy water(HDO) and heavy water is one of the origin methods to separate deuterium oxide. Distillation was just applied in the first factory built in the United States to produce heavy water, which of course was later replaced by a more economical method. Chemical method is now more commonly used and also more economical and hydrogen sulfide (HDS)-water double-temperature exchange is one of the methods to extract heavy water from seawater. The exchange proceeds as the following reactions: H2O (liquid) + HDS(gas) =HDO(liquid)+H2S.At low temperature (25℃) the deuterium in hydrogen deuterium sulfide(HDS) transfers to liquid water forming HDO and at high temperature (100℃) deuterium in HDO transfers to H2S forming HDS. The deuterium is extracted from water after such process in which the ratio of? D2O to H2S is 1:71600 and the amount of H2S is quite large but still much smaller than that of? water in vapor method. Therefore the equipment used in such method is small and the cost is low. Generally speaking it is also commercial to concentrate heavy water primarily with such method. Hydrogen sulfide gas is toxic and corrosive but this method is better than others, which is currently the most widely used.
H2S-H2O double-temperature exchange process figure
Production method
Deuterium oxide resource is very rich and the content in seawater reaches 5 × 1014t. The purity of heavy water in reactor is required to reach 99.75% while? the concentration of heavy water in natural water is very low with only 0.015% And the characteristics of heavy water production are large separation numbers, long balance time, large amount of material processing and energy consumption. The cost of heavy water production depends largely on that of initial enrichment and the chosen of concentration method from natural concentration to about 1% is very important. There are three main heavy water production methods as follows:
Distillation method: using the vapor pressure characteristic of deuterium compounds to enrich deuterium. The main raw materials are hydrogen, ammonia, water and so on. The distillation factor of liquid hydrogen is large but the low temperature technology and equipment limit the scale of production. Water distillation is easy and reliable to operate but the separation coefficient is too small with large energy consumption. The separation coefficient of ammonia distillation is slightly larger than that of water and the latent heat is small. But the limited ammonia source makes it uneconomical to be used for initial enrichment.
Electrolysis method: the electrolysis separation coefficient of deuterium is about 10. It is the main method producing deuterium oxide before the 1950’s but cannot be used? singly due to large energy consumption.
Chemical exchange method: as the the most economical way now to produce heavy water, the actual process? is divided into single-temperature and double-temperature exchange method. And the double-temperature exchange process using hydrogen sulfide and water is nowadays the main method to produce low-concentration heavy water in industrial scale. In addition there are other methods still in? development? such as hydrogen-adsorption alloy adsorption-separation method and laser separation method.
Purification Methods
Distil it from alkaline KMnO4 [de Giovanni & Zamenhof Biochem J 92 79 1963]. NOTE that D2O invariably contains tritiated water and will therefore be RADIOACTIVE; always check the radioactivity level of D2O in a scintillation counter before using.
Check Digit Verification of cas no
The CAS Registry Mumber 7789-20-0 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 7,7,8 and 9 respectively; the second part has 2 digits, 2 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 7789-20:
(6*7)+(5*7)+(4*8)+(3*9)+(2*2)+(1*0)=140
140 % 10 = 0
So 7789-20-0 is a valid CAS Registry Number.
InChI:InChI=1/H2O/h1H2/i/hD2
7789-20-0Relevant articles and documents
D2O product angular and translational energy distributions from the oxidation of deuterium on Pt(111)
Ceyer, S. T.,Guthrie, W. L.,Lin, T.-H.,Somorjai, G. A.
, p. 6982 - 6991 (1983)
The angular and translational energy distributions of D2O produced from the oxidation of deuterium on the (111) crystal face of platinum have been measured over the surface temperature range of 440-913 K.Although the angular distributions are described by a cosine function, the translational energy distributions deviate from the corresponding Maxwell-Boltzmann distributions.At the normal angle, the D2O mean translational energy /2k varies from 220 to 400 K over the temperature range investigated.Two mechanisms for the production of translationally cold product molecules are discussed.
Abel, E.,Redlich, O.,Stricks, W.
, p. 525 - 525 (1934)
Hinshelwood, C. N.,Williamson, A. T.,Wolfenden, J. H.
, p. 836 - 836 (1934)
Time-resolved in situ neutron diffraction studies of gas hydrate: Transformation of structure II (sII) to structure I (sI)
Halpern,Thieu,Henning,Wang,Schultz
, p. 12826 - 12831 (2001)
We report the in situ observation from diffraction data of the conversion of a gas hydrate with the structure II (sII) lattice to one with the structure I (sI) lattice. Initially, the in situ formation, dissociation, and reactivity of argon gas clathrate
HYDROGEN-DEUTERIUM INVERSE ISOTOPE EFFECT MEASURED FOR THE C-O BOND DISSOCIATION PROCESS IN THE METHANATION ON SUPPORTED NOCKEL CATALYSTS
Mori, Toshiaki,Masuda, Hiroyuki,Imai, Hisao,Miyamoto, Akira,Baba, Shigeo,Murakami, Yuichi
, p. 831 - 834 (1981)
A hydrogen-deuterium inverse isotope effect was found for the C-O bond dissociation process in the methanation of adsorbed CO on a Ni catalyst using a pulse technique; the average value of kH/kD was 0.75.Such an effect (0.77) was also found for the steady-state reaction of the CO methanation.It was shown that the adsorbed CO molecule is partially hydrogenated before the C-O bond dissociation.
Catalytic Oxidation and Isotopic Exchange of Hydrogen over 12-Molybdophosphoric Acid
Mizuno, Noritaka,Watanabe, Tetsuji,Misono, Makoto
, p. 890 - 894 (1990)
The reactions of H2 such as H2-D2 isotopic equilibration and exchange, reduction of catalyst by H2 (noncatalytic oxidation of H2 by a catalyst), and catalytic oxidation of H2, have been studied mostly at 573 K over 12-molybdophosphoric acid (PMo12) and it
Pure ice IV from high-density amorphous ice
Salzmann, Christoph G.,Loerting, Thomas,Kohl, Ingrid,Mayer, Erwin,Hallbrucker, Andreas
, p. 5587 - 5590 (2002)
High-density amorphous ice (HDA), made by compression of hexagonal ice at 77 K, was heated at a constant pressure of 0.81 GPa up to 195 K and its phase transition followed by displacement-temperature curves. The crystalline phases recovered at 77 K and 1
Verheij, Laurens K.,Hugenschmidt, Markus B.,Coelln, Ludwig,Poelsema, Bene,Comsa, George
, p. 523 - 530 (1990)
Anton, A. Brad,Cadogan, David C.
, p. L548 - L560 (1990)
Model reaction studies on vanadium oxide nanostructures on Pd(111)
Kratzer,Surnev,Netzer,Winkler
, (2006)
Deuterium desorption and reaction between deuterium and oxygen to water has been studied on ultrathin vanadium oxide structures prepared on Pd(111). The palladium sample was part of a permeation source, thus enabling the supply of atomic deuterium to the sample surface via the bulk. Different vanadium oxide films have been prepared by e-beam evaporation in UHV under oxygen atmosphere. The structure of these films was determined using low energy electron diffraction and scanning tunneling microscopy. The mean translational energy of the desorption and reaction products has been measured with a time-of-flight spectrometer. The most stable phases for monolayer and submonolayer VO x are particular surface-V2O3 and VO phases at 523 and 700 K, respectively. Thicker films grow in the form of bulk V 2O3. The mean translational energy of the desorbing deuterium species corresponds in all cases to the thermalized value. Apparent deviations from this energy distribution could be attributed to different adsorption/desorption and/or accommodation behaviors of molecular deuterium from the gas phase on the individual vanadium oxide films. The water reaction product shows a slightly hyperthermal mean translational energy, suggesting that higher energetic permeating deuterium contributes with higher probability to the water formation.
Synthesis of OH from reaction of O and H on the Rh(100) surface
Gurney, Bruce A.,Ho, W.
, p. 5562 - 5577 (1987)
We report the synthesis of the OH intermediate from O and H coadsorbed on the Rh( 100) surface at 90 K and heated in ultrahigh vacuum ( UHV ) to between 140 and 240 K; the species is stable when cooled again to 90 K.When heated to higher than 240 K H2O is formed and evolved from the surface, demonstrating that OH formation is an important step in H20 synthesis.Temperature programmed electron energy loss spectroscopy (TP-EELS), temperature programmed reaction spectroscopy (TPRS), and low energy electron diffraction ( LEED ) were employed in the study of this intermediate.The EEL spectra of the OH species is characterized by a stretch mode at 394 meV, bending mode at 114 meV, frustrated lateral translation at 82 meV, and frustrated vertical translation at 54 meV.Off-specular measurements show that the OH bending mode is entirely dipole active at an impact energy of 6 eV.By monitoring the OH bend intensity normalized to the elastic intensity as the crystal temperature is linearly ramped, the kinetics of both OH synthesis and OH combination to form Hz0 was probed.Kinetics was obtained using the heating rate variation method (from the shift in the temperature of fastest reaction Tp with heating rate) and the coverage variation method ( from the shift in Tp resulting from different reactant concentrations ) .An activation energy of Ef = 4+/-1 kcal mol-1 for OH formation was obtained.We find a half order coverage dependence indicating that OH formation occurs at the perimeters of O islands.An activation energy of Ec = 24+/-1 kcal/mol-1 was obtained for the combination reaction.Isotopic substitution of deuterium ( D ) for hydrogen yielded no OD or D2O under UHV conditions, but an O covered surface heated in a D2 pressure 10-8 Torr formed both surface OD and evolved D2O.This difference in H and D reactivity can be explained by the combination of the observed inverse kinetic isotope effect (KIE) in D2 recombinative desorption (in which D2 desorbs faster than H2) and the observed normal KIE in OD formation ( in which OD forms at a slower rate than OH ) .
Kinetics of hydrogen oxidation to water on the Rh(111) surface using multiple source modulated molecular beam techniques
Padowitz,Sibener
, p. 125 - 143 (1991)
We have examined the kinetics of the oxidation of hydrogen to water on the Rh(111) surface using modulated molecular beam reactive scattering. For reactant pressures below 10-4 Torr and temperatures from 450-1250 K we observe serial steps, with apparent activation energies of 2.5 ± 1 and 10 ± 1 kcal/mol. Pseudo-first-order preexponential factors are 105 and 107 s-1, respectively, varying slightly with oxygen coverage. Reaction is inhibited by excess oxygen. Maximum water production occurs around 650 K. At lower temperatures the reaction becomes nonlinear. We use a new three-molecular-beam arrangement. Two continuous, independently adjustable beams establish steady-state surface concentrations, while a weaker modulated third beam induces small concentration perturbations around the selected steady state. With this technique we varied surface oxygen coverages, used isotopic substitution in the three beams to produce H2O, D2O and HDO, and linearized the HDO reaction.
Concerted Multiproton-Multielectron Transfer for the Reduction of O2to H2O with a Polyoxovanadate Cluster
Brennessel, William W.,Fertig, Alex A.,Matson, Ellen M.,McKone, James R.
, p. 15756 - 15768 (2021/10/02)
The concerted transfer of protons and electrons enables the activation of small-molecule substrates by bypassing energetically costly intermediates. Here, we present the synthesis and characterization of several hydrogenated forms of an organofunctionalized vanadium oxide assembly, [V6O13(TRIOLNO2)2]2-, and their ability to facilitate the concerted transfer of protons and electrons to O2. Electrochemical analysis reveals that the fully reduced cluster is capable of mediating 2e-/2H+ transfer reactions from surface hydroxide ligands, with an average bond dissociation free energy (BDFE) of 61.6 kcal/mol. Complementary stoichiometric experiments with hydrogen-atom-accepting reagents of established bond strengths confirm that the electrochemically established BDFE predicts the 2H+/2e- transfer reactivity of the assembly. Finally, the reactivity of the reduced polyoxovanadate toward O2 reduction is summarized; our results indicate a stepwise reduction of the substrate, proceeding through H2O2 en route to the formation of H2O. Kinetic isotope effect experiments confirm the participation of hydrogen transfer in the rate-determining step of both the reduction of O2 and H2O2. This work constitutes the first example of hydrogen atom transfer for small-molecule activation with reduced polyoxometalates, where both electron and proton originate from the cluster.
Temperature-induced polymorphism in methyl stearate
Liu,Gibbs,Nichol,Tang,Knight,Dowding,More,Pulham
, p. 6885 - 6893 (2018/11/21)
The crystallisation of methyl stearate under a range of crystallisation conditions has been studied and three new polymorphs have been identified and structurally characterised. Form III (monoclinic, space group Cc, Z = 8) was obtained at room temperature by slow evaporation of a saturated solution in CS2. Form IV (monoclinic, space group C2/c, Z = 4) was obtained by slow cooling of the melt. Both structures were characterised by single crystal X-ray diffraction. Form V (monoclinic, space group Cc, Z = 4) was obtained from the melt by rapid cooling. X-ray and neutron powder diffraction methods were employed in the determination of this structure. Form V shows highly anisotropic thermal expansion, with expansion along the crystallographic b-axis being substantially greater than along the other two axes.