A layered mesoporous SAPO-34 prepared by using as-synthesized SBA-15 as silica source

A layered mesoporous SAPO-34 with particle size of about 20 μm was synthesized by using as-synthesized SBA-15 as silica source. For comparison, another three synthesis system were adopted to form SAPO-34 by using stoichiometric equivalence of calcined SBA-15, physical mixture of calcined SBA-15 and P123, and physical mixture of colloidal silica and P123 as initial reactants, respectively. The result shows that SAPO-34 can be prepared by all of the synthesis systems, however, only the sample prepared with as-synthesized SBA-15 shows mesoporous structure as revealed by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Compared with SAPO-34 prepared with conventional and the above three contrasting systems, the specific surface area of this sample is considerably improved due to the existence of mesoporous structure. For the application as the catalyst for methanol to olefins (MTO) reaction, the layered mesoporous SAPO-34 presents the longest single life among all of samples.