Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2019
Thesis Language: Turkish
Student: PINAR ÇİTLİ
Supervisor: NURAY OKTAR
Abstract:In the scope of M.Sc. thesis, hydrogen, which is a clean and sustainable energy source, was produced by the dehydrogenation reaction of ethane in the presence of mesoporous alumina supported catalysts. Not only COx-free hydrogen was produced by non-oxidative dehydrogenation of ethane, but also ethylene, which is an important raw material for the petrochemical industry was produced. In this study, mesoporous alumina (MA) support materials were synthesized using the hydrothermal (EISA) method. Zirconium was added to the catalyst structure by one-pot synthesis method to increase the thermal stability of the catalysts. Chromium and molybdenum, which are active metals in the ethane dehydrogenation, are loaded into the structure of mesoporous alumina and zirconium-alumina (Zr-MA) by impregnation method. Characterization techniques such as N2 adsorption-desorption, XRD, pyridine adsorbed DRIFTS and SEM-EDS analysis were performed to determine the structural and physical properties of the catalysts. The activity tests of the catalysts were initially carried out at low temperature in the microwave heated reactor system, which is achieved more efficient energy utilization than the conventional heating system. The effect of Zr, Cr and Mo metals loaded on catalysts in different ratios on catalyst activity was investigated. As a result of the activity tests, addition of zirconium to the structure increased catalyst activity as well as stability. Mo containing catalysts showed higher activity than Cr containing catalysts. The effect of reaction temperature on conversion was investigated in the presence of 25Mo@10Zr-MA catalyst, which showed the highest activity in previous studies. Furthermore, some activity tests were further carried out at 650°C in the conventionally heated reactor system. The activity test results have shown that ethane conversion over 5Cr@10Zr-MA and 5Mo@10Zr-MA catalysts at 450°C in the microwave heated reactor system reached to 45% and 53%, while the conversion over the same catalysts at 650°C in the conventionally heated reactor system was obtained as 33% and 43%, respectively.