Preparative Hydrocarbon Compound Type Analysis by High Performance Liquid Chromatography

New pitches with enhanced graphitization ability obtained from Moroccan oil shales

“…The mixture was filtered and the solid residue extracted in a Soxhlet apparatus with chloroform for 12 h. After removing the solvent under reduced pressure, the organic materials were combined, dried for 12 h at 40 • C and weighed. The recovered oil was treated with n-hexane (in a 1/10 oil to solvent mass ratio) [11], in order to precipitate the high molecular weight fraction. After stirring for 12 h, the two fractions, soluble (maltenes) and insoluble (asphaltenes), were separated by filtration through Whatman paper and dried for 12 h at 40 and 80 • C, respectively.…”

Liquid chromatographic separation of aromatic hydrocarbons with chemically bonded (2,4-dinitroanilinopropyl)silica

“…Although the separation schemes are widely varied, they generally involve a preliminary separation ZLCcording to functional groups such as acids, bases, and neutrals (hydrocarbons) followed by subsequent fractionation of the functional-group types into compound classes (1-3). Highperformance liquid chromatographic (HPLC) fractionation of the neutral compounds in liquid fossil fuels into compowid classes has received considerable attention (4)(5)(6)(7)(8)(9)(10). However, even with the large effort expended on these HPLC separations, the aromatic-ring number separation of high boiling or residuum hydrocarbons/neutrals from petroleum, coal liquids, and shale oils stdl represents a formidable task.…”

A detailed study of the microwave pyrolysis of the Moroccan (Youssoufia) rock phosphate

“…After 8 h of stirring, the two fractions, soluble (maltenes) and insoluble (asphaltenes) were separated by filtration with number 2 Whatman paper. The maltenes were fractionated according to a standard procedure [38] in an 80 cm long and 1.5 cm diameter silica gel (70-230 mesh) column. Elution of paraffins, aromatics, and of polar compounds was performed with hexane, a mixture of hexane-dichloromethane (90:10 v/v) and methanol, respectively.…”