Dortmund Data Bank
Encyclopedia
The Dortmund Data Bank is a factual data bank for thermodynamic and thermophysical data. Its main usage is the data supply for process simulation
Process simulation
Process simulation is used for the design, development, analysis, and optimization of technical processes and is mainly applied to chemical plants and chemical processes, but also to power stations, and similar technical facilities.- Main principle :...

 where experimental data are the basis for the design, analysis, synthesis, and optimization of chemical process
Chemical process
In a "scientific" sense, a chemical process is a method or means of somehow changing one or more chemicals or chemical compounds. Such a chemical process can occur by itself or be caused by somebody. Such a chemical process commonly involves a chemical reaction of some sort...

es. The DDB is used for fitting parameters for thermodynamic models like NRTL  or UNIQUAC
UNIQUAC
UNIQUAC is an activity coefficient model used in description of phase equilibria.The model is a so-called lattice model and has been derived from a first order approximation...

 and for many different equations describing pure component properties like e. g. the Antoine equation for vapor pressures. The DDB is also used for the development and revision of predictive methods like UNIFAC
UNIFAC
The UNIversal Functional Activity Coefficient method is a semi-empirical system for the prediction of non-electrolyte activity estimation in non-ideal mixtures. UNIFAC uses the functional groups present on the molecules that make up the liquid mixture to calculate activity coefficients...

 and PSRK
PSRK
PSRK is an estimation method for the calculation of phase equilibria of mixtures of chemical components. The original goal for the development of this method was to enable the estimation of properties of mixtures which contain supercritical components...

.

Mixture Properties

  • Phase equilibria data (vapor-liquid
    Vapor-liquid equilibrium
    Vapor–liquid equilibrium is a condition where a liquid and its vapor are in equilibrium with each other, a condition or state where the rate of evaporation equals the rate of condensation on a molecular level such that there is no net vapor-liquid interconversion...

    , liquid-liquid
    Liquid-liquid extraction
    Liquid–liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid phase into another liquid...

    , solid-liquid), data on azeotropy
    Azeotrope
    An azeotrope is a mixture of two or more liquids in such a ratio that its composition cannot be changed by simple distillation. This occurs because, when an azeotrope is boiled, the resulting vapor has the same ratio of constituents as the original mixture....

     and zeotropy
  • Mixing enthalpies
  • Gas
    Gas
    Gas is one of the three classical states of matter . Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons...

     solubilities
  • Activity coefficient
    Activity (chemistry)
    In chemical thermodynamics, activity is a measure of the “effective concentration” of a species in a mixture, meaning that the species' chemical potential depends on the activity of a real solution in the same way that it would depend on concentration for an ideal solution.By convention, activity...

    s at infinite dilution
  • Heat capacities
    Heat capacity
    Heat capacity , or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount...

     and excess heat capacities
  • Volumes, densities, and excess volumes (volume effect of mixing)
  • Salt
    Salt
    In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...

     solubilities
  • Octanol-Water partition coefficient
    Partition coefficient
    In chemistry and the pharmaceutical sciences, a partition- or distribution coefficient is the ratio of concentrations of a compound in the two phases of a mixture of two immiscible solvents at equilibrium. The terms "gas/liquid partition coefficient" and "air/water partition coefficient" are...

    s
  • Critical data
    Critical point (thermodynamics)
    In physical chemistry, thermodynamics, chemistry and condensed matter physics, a critical point, also called a critical state, specifies the conditions at which a phase boundary ceases to exist...



The mixture data banks contain currently (April 2007) approx. 308,000 data sets with 2,157,000 data points for 10750 components building 84870 different binary, ternary, and higher systems/combinations.

Pure Component Properties

  • Saturated vapor pressures
    Vapor pressure
    Vapor pressure or equilibrium vapor pressure is the pressure of a vapor in thermodynamic equilibrium with its condensed phases in a closed system. All liquids have a tendency to evaporate, and some solids can sublimate into a gaseous form...

  • Saturated densities
  • Viscosities
    Viscosity
    Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...

  • Thermal conductivities
    Thermal conductivity
    In physics, thermal conductivity, k, is the property of a material's ability to conduct heat. It appears primarily in Fourier's Law for heat conduction....

  • Critical data
    Critical point (thermodynamics)
    In physical chemistry, thermodynamics, chemistry and condensed matter physics, a critical point, also called a critical state, specifies the conditions at which a phase boundary ceases to exist...

     (Tc, Pc, Vc)
  • Triple point
    Triple point
    In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases of that substance coexist in thermodynamic equilibrium...

    s
  • Melting point
    Melting point
    The melting point of a solid is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at standard atmospheric pressure...

    s
  • Heat capacities
    Heat capacity
    Heat capacity , or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount...

  • Heats of fusion, sublimation and vaporization
  • Heats of formation and combustion
    Heat of combustion
    The heat of combustion is the energy released as heat when a compound undergoes complete combustion with oxygen under standard conditions. The chemical reaction is typically a hydrocarbon reacting with oxygen to form carbon dioxide, water and heat...

  • Heats and temperatures of transitions for solids
  • Speed of sound
    Speed of sound
    The speed of sound is the distance travelled during a unit of time by a sound wave propagating through an elastic medium. In dry air at , the speed of sound is . This is , or about one kilometer in three seconds or approximately one mile in five seconds....

  • P-v-T data including virial coefficient
    Virial coefficient
    Virial coefficients B_i appear as coefficients in the virial expansion of the pressure of a many-particle system in powers of the density, providing systematic corrections to the ideal gas law...

    s
  • Energy functions
  • Enthalpies
    Enthalpy
    Enthalpy is a measure of the total energy of a thermodynamic system. It includes the internal energy, which is the energy required to create a system, and the amount of energy required to make room for it by displacing its environment and establishing its volume and pressure.Enthalpy is a...

     and entropies
    Entropy
    Entropy is a thermodynamic property that can be used to determine the energy available for useful work in a thermodynamic process, such as in energy conversion devices, engines, or machines. Such devices can only be driven by convertible energy, and have a theoretical maximum efficiency when...

  • Surface tension
    Surface tension
    Surface tension is a property of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects to run on the water surface...

    s


The pure component properties data bank contains currently (April 2007) approx. 157,000 data sets with 1,080,000 data points for 16700 different components.

Data Sources

The DDB is a collection of experimental data published by the original authors. All data are referenced and a quite large literature data bank is part of the DDB, currently containing more than 92,000 articles, books, private communications, deposited documents from Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

 (VINITI), the Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

 (Ukrniiti) and other former USSR states, company reports (mainly from former GDR
German Democratic Republic
The German Democratic Republic , informally called East Germany by West Germany and other countries, was a socialist state established in 1949 in the Soviet zone of occupied Germany, including East Berlin of the Allied-occupied capital city...

 companies), theses, patents, and conference contributions.

Secondary sources like data collections are normally neglected and only used as a literature source. Derived data are also not collected with the main exception of the azeotropic data bank which is built partly from evaluated vapor-liquid equilibrium data.

History

The Dortmund Data Bank was founded in the 1970s at the University of Dortmund in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

. The original reason for starting a vapor-liquid phase equilibria data collection was the development of the group contribution method
Group contribution method
A group contribution method is a technique to estimate and predict thermodynamic and other properties from molecular structures.- Introduction :In today's chemical processes hundreds of thousands of components are used...

 UNIFAC
UNIFAC
The UNIversal Functional Activity Coefficient method is a semi-empirical system for the prediction of non-electrolyte activity estimation in non-ideal mixtures. UNIFAC uses the functional groups present on the molecules that make up the liquid mixture to calculate activity coefficients...

 which allows to estimate vapor pressures of mixtures.

The DDB has since been extended to many other properties and has increased dramatically in size also because of intensive (German) government aid. The funding has ended and the further development and maintenance is performed by DDBST GmbH, a company founded by members of the industrial chemistry chair of the Carl von Ossietzky
Carl von Ossietzky
Carl von Ossietzky was a German pacifist and the recipient of the 1935 Nobel Peace Prize. He was convicted of high treason and espionage in 1931 after publishing details of Germany's alleged violation of the Treaty of Versailles by rebuilding an air force, the predecessor of the Luftwaffe, and...

 University of Oldenburg, Germany.

Additional contributors are the DECHEMA
DECHEMA
DECHEMA stands for "Gesellschaft für Chemische Technik und Biotechnologie" .Founded in 1926, this is a non-profitmaking organization based in Frankfurt. It has over 5000 chemists, biotechnologists and engineers as members...

, the FIZ CHEMIE (Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

), the Technical University
Tallinn University of Technology
Tallinn University of Technology is the only university of technology in Estonia, and one of the three most important institutions of higher education in Estonia generally. It is located in the capital city of Tallinn, Estonia...

 in Tallinn
Tallinn
Tallinn is the capital and largest city of Estonia. It occupies an area of with a population of 414,940. It is situated on the northern coast of the country, on the banks of the Gulf of Finland, south of Helsinki, east of Stockholm and west of Saint Petersburg. Tallinn's Old Town is in the list...

, and others.

Availability

The Dortmund Data Bank is distributed by DDBST GmbH as in-house software. Many parts of the Dortmund Data Bank are also distributed as part of the DETHERM data bank which is also available online.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK