This article concerns the design of a prototype information system for solv
ent extraction of metals including a comprehensive factual database and an
expert system to analyse experimental extraction data. A demonstration vers
ion of the solvent extraction database is described. Each database record c
orresponds to one extraction equilibrium and contains three information par
ts (bibliographic, extraction system description and extraction properties)
including chemical structural 2D and 3D information for extractants, as we
ll as thermodynamic and kinetic data in textual, numerical and graphical fo
rms. As expert system we use the Substructural Molecular Fragments method w
hich models structure-property relationships using information retrieved fr
om the database. Its performance is assessed on the distribution ratios of
Hg, In and Pt extracted by 26 phosphoryl-containing monopodands, and of ura
nium extracted by 32 mono- and tripodands or by 22 monoamides.