Improved separation and quantitative determination of hydrocarbon types in gas oil by normal phase high‐performance TLC with UV and fluorescence scanning densitometry

Abstract

Improved separation and quantitative determination of hydrocarbon types in gas oil by normal phase high-performance TLC with UV and fluorescence scanning densitometry Improved methods for separation and quantitative determination of hydrocarbon types from gas oil have been developed, which were based on high-performance thin-layer chromatography with ultraviolet and fluorescence scanning densitometry using horizontal elution. One of the methods allows the separation, detection, and determination of alkanes and naphthenes to be carried out, using berberine-impregnated silica gel HPTLC plates, elution with n-hexane, and berberine-induced fluorescence detection at 365 nm. Another developed method allows total aromatics to be determined using silica gel HPTLC plates by elution with n-hexane and acetone, and UV detection. In turn, PACs over three aromatic rings can be determined on either silica gel or caffeine-impregnated silica gel HPTLC plates, elution with n-hexane, and selective detection using native fluorescence at 365 nm. Concentrations lower than 5 wt% can be determined using this technique. In addition, a technique for an efficient, baseline-resolved separation of a gas oil according to the number of aromatics rings (mono + di-, tri-, and polyaromatic compounds with more than three rings) is presented here. This technique involves a multistep elution on a mixed (silica gel and caffeine-impregnated silica gel HPTLC plate) using a counter-elution device, and UV detection.

Changes in Fluorescent Emission Due to Non‐covalent Interactions as a General Detection Procedure for Thin‐Layer Chromatography

“…As shown throughout this work, fluorescent response depends on the balance between non-specific and specific interactions in each particular case between probe and analyte in the medium considered. For a given system, it has been reported that the sign and magnitude of analyte response can be tailored by modification of chromatographic parameters: [4,6,7] probe concentration, scanning beam size, probe structure and its optical characteristics (l exc and l em ), sample structure, sample concentration and application volume. Additionally, the development length and sample application system have an influence on peak width, and hence detection sensitivity, and also influence the fluorescent response.…”

“…[2 ,4-6] For example, a TLC method has been developed for separating and determining saturated hydrocarbons in fossil-fuel products by fluorescence scanning densitometry, through pre-or post-impregnation of silica gel plates with berberine or coralyne salts. [7] The aim of recent work by us [8] was to develop original HPTLC-based methods for separating lipids, using FDIC for detection. FDIC was used here in combination with different automated multiple development (HPTLC/AMD) strategies for separating lipids on silica gel plates.…”

Influence of reaction parameters on brown coal–polyolefinic plastic co-pyrolysis behavior

“…7. According to [19,25] the obtained data can be interpreted as a distribution of aromatic and heteroaromatic hydrocarbons. Chromatograms show that co-hydropyrolysis products are characterised by higher content of benzene derivatives (region A in Fig.…”

Coralyne cation, a fluorescent probe for general detection in planar chromatography

“…Saturated hydrocarbons produce increases in berberine or Reichardt's dye emission [2]. It has been possible to use this phenomenon in HPTLC-scanning fluorescence mode, by impregnating silica gel plates with the above-mentioned probes for determining saturated hydrocarbons in different types of fuels [5,6]. Fluorescent responses in these systems depend on analyte structure through the interactions that they establish with the corresponding probe.…”