Solvent extraction database

Solvent extraction Database SXD. 2006. http //infochim.u-strasbg.fr/sxd. 

Solvent extraction Database (SXD) software has been developed by A. Varnek et al.51 Each record of SXD corresponds to one extraction equilibrium and contains 90 fields to store bibliographic information, system descriptions, chemical structures of extractants, and thermodynamic and kinetic data in textual, numerical, and graphical forms. A search can be performed by any field including 2D structure. SXD tools allow the user to compare plots from different records and to select a subset of data according to user-defined constraints (identical metal, content of aqueous or organic phases, etc.). This database, containing about 3,500 records, is available on the INTERNET (http //infochim.u-strasbg.fr/sxd). 

Since the 1940s, a great number of papers have been reported that are relevant to solvent extraction. The best way to use these data is to make a database for solvent extraction. The database for the solvent extraction of metal ions now available through the Internet is Solvent Extraction DATAbase (SEDATA) (http //sedatant. chem.sci.osaka-u.ac.jp/) [41], which was originally constructed by Suzuki et al. 

An INTERNET compatible database for solvent extraction of metal ions (SEDATA), developed by H. Watarai et al., contains about 9,600 equilibrium constants, including distribution constants, extraction constants, and adduct formation constants, for more than 1,400 ligands and 82 metal ions.50 Raw data points of extraction curves are also incorporated to be reconstructed as a figure. However, SEDATA contains no fields for 2D chemical structures of extractants and allows one to perform a search using only eight fields (classification, metal, valence, reagent, solvent, title of the paper, author, and year). 

Watarai, H. Fujiwara, M. Tsukahara, S. Suzuki, N. Akiba, K. Saitoh, K. Hasegawa, Y. Kato, M. Construction of an INTERNET compatible database for solvent extraction of metal ions. Solvent Extr. Res. Dev. Jpn. 2000, 7, 197-205. 

Peak numbers correspond to those in Figures i and 2 and Table II. RI, retention index. Average relative conccniratiop t. standard deviation (n=I2). SDE, simultaneous steam distillation-solvent extraction. DE, direct solvent extraction. Compound tentatively identified by comparing its mass spectrum to Wiley 13SK mass spectral database, Compound not previously identified in saffron. Compound positively identified as described in materials and methods. V trace. Compound tentatively identified by comparing its mass spectrum with published literature (II). nd. not detected. I.S., internal standard, N/A, not available, peak could not be resolved. 

Plasticizers are attached to the polymer by weak physical bonds rather than chemical ones, so can be separated readily by solvent extraction. A suitable solvent should selectively dissolve the plasticizer from the polymer. Methanol is frequently employed. Excess methanol should be dried off at 105°C. Infrared spectroscopy can be used to identify plasticizers by smearing the sample on one side of a KBr tablet and running a transmission spectrum or by examining the neat extract by ATR-FTIR spectroscopy. The resulting spectra can be compared with those in a specialized database of additives (Scholl, 1981). 

The construction of literature databases has been carried out after the format of the personal database system TOOL-IR-PDB/Orion, which was initially designed as the sub-system of the database management system TOOL-IR in the Computation Center of the University of Tokyo. This personalliterature database system has been applied to construct several chemical databases including those for solvent extraction, nuclear magnetic resonance spectroscopy, abstracts and preprints of some important domestic symposia held in Japan, etc. [3]. 

This analysis illustrates the utility of supercritical fluids for rapid selective extraction with no expensive solvent disposal problems, K IDS for molecular weight information, and the usage of on-line databases to assist in data interpretation. 

The solute descriptors are required in the system coefficient approach. The solute descriptors can be found in Abraham s databases for many compounds. Commercial software (Absolv Pharma Algorithms, Ontario, Canada) is also available for estimating the values of the solute descriptors from the struemre of the compounds. Experimental determination of the solute descriptors is best carried out through the use of multiple water/solvent partition coefficients (Abraham et al., 1999). However, it is difficult to determine the water/solvent partition coefficients using the traditional hquid-hquid extraction, which involves tedious manual operation, compheated sample handhng, and emulsion problems. 

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