The Preparation Of Pt-based Catalysts And Research Of Catalytic Activity For Perhydrofluorene Dehydrogenation

In numerous new energy, hydrogen which is clean, efficient, safe, abundant and renewable energy can be obtained by one-time, twice and reproducible resources. Therefore, hydrogen is regarded as the ideal energy to solve the shortage of fossil energy. However, the hydrogen storage technology is restricts the process of hydrogen to achieve large-scale application.Pt/γ-Al2O3is a typical dehydrogenation catalysts, but Pt content of the catalyst is very large. So by adding a second metal in the preparation of bimetallic catalyst solve this problem which reduce the amount of noble metal and obtain low cost recycling catalyst with high conversion rate and high stability. The second metal may influence the first metal through electronic interactions or be involved in the reaction by bonding directly to reactants or inter-mediates. The second metal may substantially suppress the amount of hydrogen chemisorbed on the surfaces of bimetallic particles, much as it affects the catalytic properties for some reactions. The typical catalyst of loading with precious metal, the carrier play a very important role. In addition to large specific surface area, structure characteristics of carrier has a direct impact on the performance of catalyst. Therefore, the preparation of dehydrogenation catalyst of important research is modification and optimization of carrier.This paper has carried out the bimetallic catalyst Pt-M/γ-Al2O3(M=Sn, Ce and Cr) and Pt/MIL-101. These catalytic properties over liquid organic perhydrofluorene (PHF) have been elaborately investigated.The primary contents and results are as follows:1. Pt-M/γ-Al2O3(M=Sn, Ce and Cr) was employed as a support for preparing nanoparticle platinum catalysts by incipient impregnation method, which was used as a catalyst in the liquid phase perhydrofluorene dehydrogenation and exhibited considerable activity. The2.5wt.%Pt-0.5wt.%Sn/γ-Al2O3catalyst2.5wt.%Pt-0.5wt.%Ce/y-Al2O3catalyst,2.5wt.%Pt-2.5wt.%Cr/γ-Al2O3catalyst resulted in a maximum PHF dehydrogenation capacity of6.67wt.%,6.64wt.%,6.61wt.%with the PHF dehydrogenation conversion over98%, significantly higher than that obtained for other catalysts. The calcined temperature increased, dehydrogenation conversion of PHF increased before they are reduced, the optimized calcined temperature is500℃with the PHF dehydrogenation conversion over98%. Compared with other two kinds of added metal, the reaction rate of Sn is quick, catalytic activity is better than others. Illustrate that add a second metal to Pt/γ-Al2O3catalyst could greatly increase its activity and conversion of perhydrofluorene could be raised, and also accelerated the rate of dehydrogenation. 2. Highly pure metal organic framework MIL-101is synthesized by varying synthetic conditions. Pt/MIL-101catalysts were prepared by loading platinum onto the MIL-101using the incipient wetness impregnation method by hydrogen reduction. The uniform dispersion and small particles with the size mainly between2and3nm were found for the catalyst samples with Pt/MIL-101. Catalytic performance of Pt/MIL-101is better by secondary dipping preparation, the metal dispersion of samples were evenly and widely, EDS analysis data can also be learned that the Pt particles were obviously, this explains that the catalyst performance of secondary dipping preparation were better. We are also study that catalytic activity of hygrogen with different amount of catalyst:when we add0.05g of catalysts, dehydrogenation conversion of PHF is higher than others, PHF dehydrogenation capacity is6.25wt.%, the PHF dehydrogenation conversion is92.69%. We were investigated that different carrier preparation of catalysts. Pt/MIL-101is better than Pt/γ-Al2O3. PHF dehydrogenation capacity of Pt/γ-Al2O3is8.83wt.%, the PHF dehydrogenation conversion is86.43%.