Different materials such as sepiolite (magnesiumsilicate), amorphous silico-alumino-phosphate (ASAPO) or other mixed oxides such as SiO2-ZrO2, or SiO2-Al2O3-MgO, are studied as potential active matrix components of a FCC catalyst, with the final objective of maximizing the light cycle oil (LCO) yield while minimizing the aromatic content of this fraction. The physico-chemical characteristics of these materials as well as their hydrothermal stability play a decisive role in their catalytic behavior. The high surface area amorphous SAPO stands out presenting high selectivity to LCO while decreasing the aromatics content as compared to a commercial SiO2-Al2O3 used as reference material. A formulation has been simulated using this material and, after equilibration, its catalytic behavior has been compared to that of a conventional FCC catalyst formulation. (C) 2007 Elsevier B.V. All rights reserved.