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With the worsening environmental problems caused by the greenhouse effect, the study of fuel alternatives generated by non-fossil sources has intensifi ed. The incorporation of biodiesel (mono-ester of triglycerides) to petroleum diesel is an example of commercial application for reduction in the emission of fossil CO 2 and sOx and nOx as well. in this context, the generation of mixture of hydrocarbons for catalytic cracking of vegetable oils combines the advantages of the Transesterifi cation process to generate compounds such as petroleum-derived fuels such as: gasoline, kerosene and diesel. This review presents current trends in scientifi c literature for biofuels from thermal (pyrolysis) and catalytic processing. For the pyrolysis it has been described the temperatures use to obtain the fuel in the diesel range. the catalytic processing involves the heterogeneous catalysts used in the processing crude oil and the conditions of temperature and pressure. in conclusion it is showed that the cracking catalytic process allows chose what fuel does one want simply changing the catalytic that is used.Keywords: Biofuels, Pyrolysis, Hydroprocessing, vegetable oils. Producción de biocombustibles por medio de los procesos termocatalíticos de aceites vegetales: una reseña resuMenCon el empeoramiento de los problemas ambientales causados por el efecto invernadero, el estudio de combustibles alternativos generados por fuentes so fósiles ha sido intensifi cado. La incorporación de biodiesel (mono-éster de triglicéridos) a diesel de petróleo es un ejemplo de una aplicación comercial para la reducción en la emisión de CO2 fósil, sOx al igual que nOx. en este contexto, la generación de mezclas de hidrocarburos para craqueo catalítico de aceites vegetales combina las ventajas de los procesos de Transesterifi cación para generar componentes como los combustibles derivados del petróleo, como: gasolina, kerosene y diesel. esta reseña presenta las tendencias actuales en la literatura científi ca para procesos térmicos (pirolisis) y catalíticos en los biocombustibles. Para la pirolisis se han descrito las temperaturas usadas para obtener el combustible en los rangos de diesel. Los procesos catalíticos implican los catalizadores heterogéneos usados en el procesamiento del crudo y las condiciones de presión y temperatura. en conclusión se muestra que el proceso de craqueo catalítico permite elegir que combustible puede buscarse simplemente cambiando la catálisis que es usada.

This work investigates the effect of NaZSM-5 zeolite's acid properties on the catalytic cracking of crude soybean to produce gasoline-like hydrocarbons. We modified both the acid concentration and the acid strength of the NaZSM-5(60) zeolite (where 60 denotes the SiO 2 /Al 2 O 3 molar ratio) either by varying the SiO 2 /Al 2 O 3 ratio (i.e., 30, and 90) or by exchanging the compensation cation (i.e., from Na + to H +). Given the ammonia temperature-programmed desorption and temperatureprogrammed oxidation tests, we observed that the acid strength of the catalyst is associated not only with the distribution of the cracking products, but also with the nature of the carbonaceous deposits formed during the reaction. Weak, medium, and strong acidity were associated with the formation of heavy hydrocarbon species, soft, and hard coke, respectively. The NaZSM-5 zeolites exhibited weak and medium acidity, while the HZSM-5(60) zeolite exhibited weak and strong acidity. Although both NaZSM-5(30) and HZSM-5(60) zeolites delivered higher gasoline yield than the NaZSM-5(60) zeolite due to its higher acid concentration, the HZSM-5(60) zeolite formed carbonaceous deposits with lower reactivity (i.e., hard coke). Therefore, low values of SiO 2 /Al 2 O 3 ratio in the NaZSM-5 zeolite drive the reaction products towards gasoline-like hydrocarbons and favor the catalyst reactivation through the formation of more reactive carbonaceous deposits.