Optimización de condiciones de operación para obtener isoparafinas a partir de hexadecano com catalizadores de Pt/SO4-ZrO2 o Pt/WOx-ZrO2

M. BUSTO; C.R. VERA; J.M. GRAU

Buenos Aires, Argentina

Congreso; XVI Congreso Argentino de Catálisis; 2009

Sociedad Argentina de Catálisis

The isomerization-cracking of long paraffins for the production of high octane branched paraffins was studied in batch mode using tungsten-zirconia and sulfatezirconia catalysts. n-Hexadecane was used as model feedstock. Reactions conditions (temperatura, pressure) were varied in order to optimize the yield to isoparaffins. The results show that the optimum set of conditions for this reaction are 225°C and 15 atm. The best performing catalyst is tungsten-zirconia. Sulfate-zirconia has too high cracking activity and reduced liquid yield. Conversely tungsten-zirconia produces less C1-4 and more médium and long isoparaffins. With respect to the pressure the optimum is the same for both catalysts and a volcano plot is found. The pattern is due to the competing effect of hydrogen at high pressures. Hydrogen is needed for the hydrogenation of coke precursors but too high pressures have an inhibitory effect. The effect is attributed both to excessive chemisorption and to a reduction of the concentration of olefinic intermediates in thermodynamically constrained metal reactions.