Studies on the use of faujasite as a reagent to deliver silica and alumina in building new zeolite structures with organo-cations

The use of zeolites, in particular faujasite (FAU), as synthesis reagents to make other zeolite types has steadily increased in the past several years. In this contribution, we survey some of these research programs and review Chevron's long history in this area. By using more open (lower framework density) zeolites as reagents in combination with organic SDAs, we discovered early on that this synthesis route provided a means to change the reaction kinetics and therefore reaction times while also influencing product selectivity. Critical to our understanding of this synthetic method was determining if ion-exchange into an open structure like FAU could lower activation barriers to nucleation. To answer this question, we studied the conversion of FAU into SSZ-13 (CHA) with variable acidity, a system in which we have significant experience and synthetic data for comparison. Here, we specifically considered the ion-exchange events themselves and the zeolite reaction rates. In addition, we altered some of the synthesis events by silylation of the FAU reagents.