Estudo das influências das Características físico-químicas de zeólitas no craqueamento do óleo de soja

Abstract

Vegetable oils have been studied as raw materials to yield fuel hydrocarbons. The catalytic and thermal transformations of these oils have been presented as being able to generate hydrocarbons from which diesel oil and vegetable gasoline may be obtained. The catalysts used in these researches are usually zeolites which, after the petroleum crisis in the seventies, have been continually researched and modified, once there are great environmental restrictions to tetraethyl lead; it is required a good performance of the catalyst relative to the gasoline octane content obtained through an optimum yield of aromatic hydrocarbons and olefins. This work studies tile catalytic degradation of tile soya oil, using amorphous silica-almnina and zeolites Y, Mordenite and ZSM-5, in their protonic form, as catalysts, where it is determined the catalytic selectivity and stability, through the analysis of the composition of the reaction's resulting products and the physical chemical characteristic of the solids employed. ix The zeolites Y and ZSM-5, both with greater Brönsted acidity presented products that are rich in aromatic hydrocarbons while tile amorphous silica-alumina generated essentially paraffin hydrocarbons. The results of tile analysis as well as the physical chemical characteristics of the solids that were tested, suggest that the cracking reaction of the Soya oil occurs to a greater extent on the surface of the catalysts