Dortmund Data Bank

DDB (Dortmund Data Bank) DDBST GmbH, Germany... 

International organizations, for example, lUPAC Thermodynamics, started to collect the physical-chemical and thermodynamic properties of ILs about 10 years ago. Now, for the first time we can find massive data in two data banks Dortmund Data Bank, Germany [1] and NIST Boulder Colorado, USA [2]. 

The excess molar enthalpies at 323 K and 1.3 MPa were measured in [64] for hydrocarbons (hex-l-ene, cyclohexane, benzene, and cyclohexene) in the [C2Cilm][Tf2Nj. The negative excess enthalpies were observed (-730 J mol at Xh = 0.63) only in the mixtures with benzene, expected from the discussion about the interactions in the solution. Much more data can be found in the two existing data banks [1,2] for example, in Dortmund Data Bank, 37 systems are accessible. 

Dortmund Data Bank, University of Oldenburg, Germany, 1996-date. 

A comprehensive collection of phase equilibrium data (including vapor-liquid, liquid-liquid, and solid-liquid data) is maintained by a group headed by Prof. Juergen Gmehling at the University of Oldenburg, Germany. This collection, known as the Dortmund Data Bank, includes LLE measurements as well as NRTL and UNIQUAC fitted parameters. The data bank also includes a compilation of infinite-dilution activity coefficients. The LLE collection is available as a series of... 

To use Equation (1.5), reliable data are needed for in binary mixtures. These data are also useful in equation-of-state or corresponding-states approaches if it is desired to fit a binary parameter to improve the performance. References to many binary excess-volume data (but not the data themselves) may be found in the series of books by Wisniak and Tamir [33], and data may be found in the Dortmund Data Bank [13] and a volume of the Landolt-Bomstein series [34]. 

Some of the compilers of the DECHEMA Chemistry Data Series expanded their work into a comprehensive data bank for thermophysical property data. The Dortmund Data Bank (DDB) historically concentrated on mixtnre data, and it contains tens of thousands of datasets both for mixtnre phase eqnilibria (inclnding electrolytes) and for excess properties of mixing. In recent years, a large amonnt of pnre-component property data has also been added. 

A collection of approximately 47,400 zeotropic and azeotropic data sets, compiled from 6600 references, are stored in a comprehensive computerized data bank (Reference 10). The references from the above-mentioned compilations and from the vapor-liquid equilibrium part of the Dortmund Data Bank (Reference 11) were supplemented by references found from CAS online searches, private communications, data from industry, etc.. Over 24,000 zeotropic data and over 20,000 azeotropic data are available for binary systems. Nearly 90% of the binary azeotropic data show a pressure maximum. In most cases (ca. 90%) these are homogeneous azeotropes, and in approximately 7-8% of the cases heterogeneous azeotropes are reported. Less than 10% of the data stored show a pressure minimum. Approximately 21,000 of the data sets stored were published after 1970. 

Dortmund Data Bank — Maintains extensive databases on thermodynamic and transport properties of pure compounds and mixtures of industrial interest. The data are distributed through DECHEMA, ElZ CHEMIE, and other outlets. An abbreviated database system is also available for educational use. Address DDBST GmbH, Industriestr. 1, 26121 Oldenburg, Germany [www.ddbst.de]. 

DIPPR Pure Compound Database Dortmund Data Bank Enzyme Nomenclature Database Enzyme Structures Database European Bioinformatics Institute... 

Experimental data necessary to describe this behavior are available in large computerized data bases (e.g. Dortmund Data Bank, DDB). A small part of the data is also published in data collections (Gmehhng et al., 1977 Sorensen et al., 1979 Gmehling et al, 1986 Gmehling et al., 1988 Gmehhng et al., 2004 ). Both routes allow the calculation of VLE (see Ghapter 3.2.2.1, Sections 3.2.2.1.1 and 3.2.2.1.2) for multicomponent systems when the behavior of the binary subsystems is known. 

All the topics are illustrated with examples that are closely related to practical process simulation problems. At the end of each chapter, additional calculation examples are given to enable the reader to extend his comprehension. An introduction to a larger number of problems can be found in Qiapter 15. These problems and their solutions can be downloaded from the site www.ddbst.com. The problems partially require the use of the software Mathcad and the Dortmund Data Bank Software Package - Explorer Version. Both packages can be downloaded from the Internet. The DDBSP Explorer Version is free to use, whereas Mathcad is only available for free during a tryout period of 30 days. Mathcad files enable the users to perform the iterative calculations themselves and get a feeling for their complexity. Often, typical pitfalls in process simulation are covered in the examples, which should be helpful for the reader to avoid them in advance. 

Dortmund Data Bank www,ddbst.com. Reid, R.C., Prausnitz, J.M., and Poling, B.E. (1987) The Properties of Gases and Liquids, McGraw-Hill, New York. VDI-Gesellschaft Verfahrenstechnik und Chemieingenieurwesen (ed.) (2010) VDI Heat Atlas, 2nd edn. Springer, Berlin. 

Recently, a new method has been developed by Rarey and Nannoolal [7,8]. Based on the Dortmund Data Bank, the method has made use of all the data currently available. It has overcome the difficulties of other methods for large molecules with more than 20 carbon atoms. The calculation equations are... 

For the different hydrocarbons the parameters A, B, and C were fitted to solubility data stored in the Dortmund Data Bank and are given in Table 5.18. For the calculation of the hydrocarbon solubilities only the activity coefficient of the hydrocarbon in water at 25 "C predicted using modified UNIFAC is required. 

For solving the tasks mentioned above, reliable experimental pure component properties (vapor pressures, densities, heat capacities, transport properties, etc.) and mixture data (phase equilibria, and excess properties) for the system considered would be most desirable. Some decades ago, a time-consuming literature search was always necessary to obtain these data. In the meantime comprehensive factual data banks, for example, the Dortmund Data Bank (DDB), NIST data bank, DIPPR data bank, and so on, have been built up. These data banks contain a great part of the worldwide available experimental data. 

Table 11.1 Current status of the Dortmund Data Bank (September 2011).

T -profiles for approx. 4500 compounds are also directly available in the Dortmund Data Bank. 

Figure 11.4 Verification of Wilson parameters, with the help of experimental data stored in the Dortmund Data Bank prior to process simulation, exemplarily shown for the binary system acetone (1 )-cyclohexane (2).. 140 C, , - - 35 C, A, - - 25 C.

Table 11.3 Comparison of the predicted azeotropic data for the quaternary system carbon dioxide (1)-ethane (2)-hydrogen sulfide (3)-propane (4) at 266.5 K using VTPR with the mean value of the experimental azeotropic data stored in the Dortmund Data Bank [5, 7].

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