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A 2D-separation of 16 polyaromatic hydrocarbons (PAHs) according to the Environmental Protecting Agency (EPA) standard was introduced. Separation took place on a TLC RP-18 plate (Merck, 1.05559). In the first direction, the plate was developed twice using n-pentane at −20°C as the mobile phase. The mixture acetonitrile-methanol-acetone-water (12:8:3:3, v/v) was used for developing the plate in the second direction. Both developments were carried out over a distance of 43 mm. Further on in this publication, a specific and very sensitive indication method for benzo[a]pyrene and perylene was presented. The method can detect these hazardous compounds even in complicated PAH mixtures. These compounds can be quantified by a simple chemiluminescent reaction with a limit of detection (LOD) of 48 pg per band for perylene and 95 pg per band for benzo[a]pyrene. Although these compounds were separated from all other PAHs in the standard, a separation of both compounds was not possible from one another. The method is suitable for tracing benzo[a]pyrene and/or perylene. The proposed chemiluminescence screening test on PAHs is extremely sensitive but may indicate a false positive result for benzo[a]pyrene.

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The effect of a magnetic field on the planar chromatographic retention of some PAH has been investigated. The horizontal chamber was placed between two neodymium magnets and chromatograms were developed in the magnetic field created. The effect of the magnetic field was tested for single-component and binary mobile phases containing n -alkanes and aromatic hydrocarbons. PAH were used as solutes. The results obtained showed that magnetic fields can affect the retention and shape of the chromatographic bands of the solutes investigated. The effect depends on the type of mobile phase, the properties of the adsorbent layer and the mode of development of the chromatogram (development distance).

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Magnetic field can influence some processes taking part in the solid—liquid interphase area. An excellent tool for the investigation of this phenomenon is thin-layer chromatography. In this experiment, the influence of magnetic field parallel with chromatogram development direction on retention and system efficiency was investigated. The application of superconducting magnet allowed for generating the adjustable magnetic field up to about 2 T and allowed for investigation on dependence between inductivity of the field and retention changes of the chosen polyaromatic hydrocarbons. The obtained results show that the presence of magnetic field alternates the interactions among all components of a chromatographic system. Thus, in order to predict substance retention and system efficiency changes induced by the presence of the field, more parameters than the force acting on chromatographed molecule must be taken into account.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Heidrun Gruber-Woelfler, Marie-G. Braunbruck, Rene Laskowski, Peter W. Feenstra, Johannes G. Khinast, and Hans-Jörg Bart

The synthesis and characterization of novel stationary phases for analytical applications as well as for planar electrochromatography are presented. The stationary phases are C8-functionalized silica-based monoliths, which are supported by silica particles in order to avoid shrinkage and to increase mechanical stability. After optimizing the separation conditions in capillaries for capillary electrochromatography (CEC), the novel materials were implemented in a planar test cell and tested for the electrochromatochraphic separation of polyaromatic hydrocarbons (PAHs). Although the change of geometries implied a scale-up of the filling procedure, high separation performances with theoretical plate numbers of up to 30,000 m−1 and throughputs of 50 mL h−1 could be achieved.

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Abstract  

Solvent refined coal (SRC) produced from Indiana V feed coal was X-ray irradiated at different doses. The gases evolved from the irradiated sample consist mainly of methane, whose concentration is shown to depend on the irradiation dose. The condensed matter left after gas extraction was fractionated by column liquid chromatography into five non-polar fractions (saturated, monoaromatic, diaromatic, triaromatic and polyaromatic hydrocarbons); one of intermediate polarity (resins); and two polar (asphaltenes and asphaltols) fractions. The relative distribution of these radiolytic products depends upon the dose delivered with the concentration of hydrocarbons increasing remarkably with the dose.

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Harvey, P., Campanella, B., Castro, P., Harms, H., Lichtfouse, E., Schaffner, A., Smrcek, S. and Werck-Reichhart, D. (2002): Phytoremediation of polyaromatic hydrocarbons, anilines and phenols. Environ. Sci. Poll. Res. Int. 9, 29

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of resins, which leads to aromatic volatiles in the flame. The presence of MWCNT buckypaper accumulated the polyaromatic hydrocarbons and prevented them from pyrolysis and subsequent oxidation/combustion. The lower smoke production is also related to

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of NO x , SO x , volatile organic compounds and polyaromatic hydrocarbons [ 10 ]. Fuels investigated in this article by thermal analysis, co-firing tests, and anaerobic fermentation process, were biomass (corn and beech sawdust) and coal

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