Optimization of the preparative separation of petroleum maltenes by liquidadsorption chromatography

Liquid adsorption chromatography on classical adsorbents is most often used for the group analysis of high-boiling petroleum fractions, i.e., their se paration into saturated hydrocarbons, mono-, di- and polyaromatics, and pol ar aromatic compounds. The optimization of a preparative separation of petr oleum maltenes into the mentioned hydrocarbon compound classes by liquid ad sorption chromatography on dual silica gel-neutral alumina column was perfo rmed. Conditions of this separation, i.e., the volume of the mobile phases used, their composition and flow-rate were optimized on the base of detaile d analysis of the chromatographic fractions obtained using elemental analys is, UV spectrophotometry, H-1 NMR and vapor pressure osmometry. This optimi zation allows a substantial shortening in time of separation and separated compound class concentrates of a higher purity can be obtained. (C) 1999 El sevier Science B.V. All rights reserved.