The adsorption capacities of two synthesized zeolites (crystalline ZSM-5 and semi-crystalline faujasite Y) for a mixture of indole, quinoline and carbazole were studied. The different samples obtained show different crystalline degree, mesoporosity and Si/Al ratios. The synthesis procedure is based on the simultaneous depolymerization of a mixture of high surface area silica, such as rice hull ashes (RHA), and a crystalline zeolite, such as clinoptilolite or faujasite. The depolymerization step is followed by a partial reorganization induced by a structure-directing agent. A model mixture of nitrogenous compounds was prepared, then it was mixed with the zeolite samples and the amount adsorbed of nitrogenous compounds was determined by gas chromatography. Analysis of the adsorbed molecules reveals selectivity in favor of quinoline, followed by indole and then carbazole. The best adsorbent properties correspond to the solid with highest porous volume. The samples obtained were characterized by X-ray diffraction, 29Si and 27Al magic-angle spinning nuclear magnetic resonance, X-ray fluorescence and Fourier transform infrared spectroscopy. The Barrett-Joyner-Halenda (BJH) pore size distribution and the Brunauer-Emmet-Teller (BET) surface area values were obtained from N2 adsorption/desorption isotherms.

An updated review of the analytical techniques implemented for determining aromatic content in petroleum refining products is described here. According to our literature search, the column chromatographic (CC) method, the high pressure liquid chromatography (HPLC) and the super fluid chromatography (SFC) are the most appropriate techniques for performing this kind of analysis. HPLC and SFC techniques supply the chemical distribution of the studied fuel as additional advantage. In addition, we report mathematical relationships that can be used for convert the results obtained by one specific technique to another, convenient for comparisons between experimental and literature data.

Se presenta una revisión actualizada de los métodos analíticos implementados para la cuantificación del contenido de aromáticos en diferentes productos de refinación. De acuerdo con el análisis de la información encontrada en la literatura, los métodos de cromatografía en columna (CC), cromatografía de líquidos de alta resolución (HPLC), y cromatografía de fluidos supercríticos (SFC) son los métodos analíticos más adecuados. Los dos últimos tienen la ventaja adicional de proporcionar la distribución química del combustible estudiado. Adicionalmente, se informan relaciones matemáticas que permiten convertir los resultados de una técnica a otra lo que nos permiten realizar comparaciones entre los datos experimentales y los descritos en la literatura.

In order to find suitable applications and / or to develop new methods for processing light cycle oil (LCO), a product of Fluid Catalytic Cracking, which was formerly used as a feedstock for diesel fuel production, its chemical compound distribution along the distillation curve was obtained. Additionally, the distribution of chemical compound for six different light cycle oils from several Mexican sources and a complete physical and chemical characterization of the samples were also presented. In order to get a reliable evaluation, a new quantitative liquid chromatographic (HPLC) method was developed.

Con el objetivo de encontrar nuevas aplicaciones y/o formas de procesamiento para el aceite cíclico ligero (ACL) que es un producto de la desintegración catalítica que usualmente era empleado como componente de la carga a hidrotratamiento para la producción de diesel, se obtuvo la distribución química a lo largo de la curva de destilación. Se presenta también la distribución química y la caracterización completa de seis muestras diferentes de aceite cíclico ligero provenientes de refinerías mexicanas. Para lograr este objetivo se desarrolló un nuevo método de análisis cuantitativo utilizando cromatografía líquida de alta eficiencia (CLAE).