Speciation of Nitrogen Compounds in Gasoline and Diesel Range Process Streams by Capillary Column Gas Chromatography with Chemiluminescence Detection
| Autor: | Birbal Chawla |
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| Rok vydání: | 1997 |
| Předmět: | |
| Zdroj: | Journal of Chromatographic Science. 35:97-104 |
| ISSN: | 1945-239X 0021-9665 |
| DOI: | 10.1093/chromsci/35.3.97 |
| Popis: | This paper describes the development of a gas chromatographic method that uses nitrogen-specific detection based on chemiluminescence. A highly sensitive nitrogen-specific detector (Antek 705D) coupled to a Hewlett-Packard gas chromatograph is optimized to speciate nitrogen compounds in gasoline and diesel range process streams. Under optimized conditions, the nitrogento-carbon selectivity is greater than 106. The nitrogen chemiluminescence detector (NCD) provides a uniform response to different classes of nitrogen compounds and can detect concentration of individual components down to 100 ppb nitrogen. The detector's linear response in a range of 0.2 to 54 ppm nitrogen for an individual nitrogen component is established using several aliphatic and aromatic nitrogen-containing compounds. Gasoline and diesel range streams containing any level of total nitrogen can be analyzed after appropriate dilution so that each nitrogen component is below 50 ppm. In addition to the nitrogen speciation, total nitrogen can simultaneously be determined with reasonable accuracy using the NCD system. The repeatability and accuracy of the nitrogen quantitation is found to be within 7% at the 95% confidence level based on six to seven measurements. cess relatively inexpensive, heavy, and low-quality feed stocks containing large quantities of nitrogen and other heteroatoms' compounds. In order to obtain the desired product quality and also to understand the effect of nitrogen compounds during cat alytic processes, it is beneficial to speciate nitrogen compounds that are present in various process streams. A few attempts (1–5) have been made to identify some of the nitrogen compounds in the petroleum streams. However, in these studies, nitrogen compounds were analyzed after being concentrated using different laborious techniques such as acidtreatment extraction, ion-exchange chromatography, etc. The results of these studies are not quantitative because some of the nitrogen compounds were either not extracted or were lost during the extraction. The concentrated fractions were analyzed by gas chromatography (GC) using different detectors or gas chromatography-mass spectrometry (GC-MS). The most commonly used nitrogen detectors are Hall detec tors and nitrogen-phosphorus detectors (NPD). Hall detectors |
| Databáze: | OpenAIRE |
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