Desenvolvimento de catalisadores do tipo NiMoSAPO-5 para o uso no processo de HCC do cumeno na presença e na ausência de piridina.

Abstract

The flexibility of the Catalytic Hydrocracking (HCC) as a petroleum refining process resulted in its extraordinary growth in the last 15 years. The cause of this growth is its capacity to process loads as vacuum gas oil, recycle light oil, heavy coke gas oil, deasphalted oil or its mixtures. The increasing severity of new ambiental legislations has created a great demand for the development of new HDR catalysers, specially the catalytic hydrocracking (HCC) ones, which are better than the ones employed so far. We can emphasize that the presence of nitrogenous compounds in the petroleum loads poisons the catalysers employed on the conversion processes, forms gums and deposits, changes the color in petroleum fractions, pollutes the environment, etc. The development of new HDR catalysers can draw attention to the analysis of new active phases, new promoters or new supports. Catalysers based on Tungsten or Molybdenum Sulfides, promoted by Cobalt or Nickel, supported on -alumina are universally employed. The SAPO-5 belongs the silicoaluminophosphate family; it is a cristallin big pore microporous material, with excellent thermal and hydrothermal stability, and its acidity reaches intermediate values, between the values of zeolite an and AlPOs. The NiMo catalysers supported in SAPO-5 with different compositions were prepared through the procedure of humid impregnation of materials by the use of aqueous solutions of the Ni(NO3)2.6.H2O and (NH4)6Mo7O24.4H2O precursors, respectively. The performed characterizations were the X-ray diffraction (DRX), Temperature-Programmed Reduction (TPR), Energy-Dispersive X-Ray Spectroscopy (EDX) and Infrared Study of Piridine Adsorption. The sulfited catalysers were evaluated in the cumene hydrocracking procedure in the absence and presence of piridine. It was observed that the catalysers supported on SAPO-5 have showed a greater conversion as the percentage of impregnated Mo was raised, and that the presence of piridine was unfavorable to the performance of all the catalysers.