In this research density functional theory (DFT) calculations in combination with experimental studies are applied to the eva‎luation of the utilization of the isopropyl alcohol as a Liquid Organic Hydrogen Carrier (LOHC) and the fundamental understanding of its decomposition mechanism in the presence of platinum cluster. In the theoretical section, at first, all possible fragmentation paths for isopropyl alcohol decomposition on the surface of 13-atoms platinum cluster with D5h symmetry point were investigated. Comparing energy profiles for fragmentation paths, it was found that sequential dissociation of C2-H2 and C1-H3 bonds, resulting in propen-2-ol/hydrogen molecules is the more desirable path. Through investigation of the effect of size and symmetry of clusters on the mechanism, all paths with the lowest energy were performed in the presence of 12 and 14-atom platinum D5h cluster and 13-atoms C2v and Ih platinum cluster. It was determined that reducing the symmetry of cluster or increasing the number of constituent atoms dissociation of O-H1 and C2-H2 bonds resulting in the formation of acetone/hydrogen molecules has the most appropriate energy barrier. Also, any significant change in the decomposition mechanism was not observed by applying high symmetry 13-atoms cluster or 12-atoms clusters compared to 13-atoms cluster with D5h symmetry. Inspired by this mechanism determination and in order to demonstrate the application of platinum-based catalyst for producing hydrogen through isopropyl alcohol decomposition, a fixed bead reactor, and Pt3.4%/DFNS catalyst was selected in the experimental section. In accordance with DFT calculation outcomes, it was found out for the decomposition of isopropyl alcohol at low-temperature condition, the dehydrogenation reaction is more favorable than the dehydration which results in producing acetone and hydrogen molecules. Also with increasing the temperature, the path of decomposition changes towards the production of propene and water.

عليرضا نجفي چرمهيني

حسين فرخ پور

محمد ديناري , حسين توكل