ALUMINAS MESOPOROSAS OBTENIDAS POR LA RUTA DE LOS ATRANOS PARA SU APLICACIÓN COMO MATRICES EN CRAQUEO CATALITICO

Abstract

"The atrane route was used to synthesize aluminas that showed specific surface areas in the 150 – 275 m2/g range and average pore sizes in the 60 – 180 Å range after calcination. Different techniques were used to characterize the aluminas (IR, XRD, 27Al MAS-NMR, N2 adsorption). Crystalline micro domains of AlOOH boehmite type wereformed in the uncalcined samples that increased their size as a function of the proportion of water in the synthesis, because water favors the hydrolysis and condensation of the Al[N(CH2-CH2-O)3]2H3 complex. The calcination treatment induced the crystalline restructuration from boehmite-type to γ – alumina-type structures. The activities of the aluminas prepared by the atrane route, as indicated by the TIPB conversion at 500 °C and short reaction times from 12 to 30 s, were somewhat smaller than those observed in conventional aluminas. The apparent kinetic parameters in a simple, first order model were similar, suggesting that accessibility limitations from the pore systems were not present. The properties shown by these aluminas synthesized by the atrane route indicated a preliminary appropriate condition for being used as FCC catalyst matrices."