Synthesis of MgO-Al₂O₃/ZSM-5 by solid state reaction for propane Dehydrogenation

Solid-state grinding is a simple and effective method to introduce guest species into the channels of microporous materials through filling. The structure and the surface acidity of the materials were obtained from BET isotherms and NHj-TPD, respectively. XRD, UV-vis, UV diffuse-reflectance, and TEM were used to characterize the phases, and the morphology, respectively. The clustered layers of MgO-Al₂O₃ phases were formed in the internal pore surface and were highly dispersed inside the channels of the ZSM-5 host. So the volume of Mg0-Al₂0₃/ZSM-5 composite was larger than the ZSM-5 zeolite itself and some mesoporous channels appeared when Mg/Al species entered the channels. Meanwhile, new acid sites emerged in MgO-Al₂O₃/ZSM-5 composite and the acid amount of the sample changed. The improved Pt dispersion and the increased acid content would cause the increase of propane conversion and the modification of selectivity during the reaction.