Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı 2

Development of Efficient Catalysts for Oxy-CO₂ Reforming of Methane
Hydrogen, which can be used in many fields without polluting the environment, is thought to be the cleanest fuel source of 21th century. Therefore, low cost production, facile storage and transportation of hydrogen are important research subjects that are studied by many universities and related commercial facilities.
Nowadays, steam-hydrocarbon reforming is the major hydrogen production process. However, this process has many disadvantages like high energy demand and complicated equipment design etc. For this reason, there have been many researches to develop alternative processes for several decades and catalytic partial oxidation has come forth as a good alternative. Thus, by lowering the total investment and production costs, hydrogen production cost could be lowered.
Methane has seemed to be the best hydrocarbon source for Oxy-CO₂ reforming process because methane is the main component in natural gas and natural gas is abundant on earth. Additionally, methane has the property of having the highest H/C (H/C=4) ratio in hydrocarbons.
Researchers have tested many catalysts for reforming of methane and have seen that noble based metals catalysts (Rh, Pt, Ru, Ir) and nickel (Ni) based catalysts are active and selective for this reaction. Although, noble metal based catalysts are stable and active, because of their high cost and low availability, the best alternative have thought to be nickel based catalysts. But these catalysts have disadvantages like sintering, coking and phase transformation.
To solve these problems, catalysts that 10% (by weight) Ni loaded on different supports were prepared by using impregnation method, were characterised and their performances were investigated for Oxy-CO₂ Reforming of Methane reaction. While they showed the highest CH₄ and CO₂ conversions under the flow rate of 15000 l/kg hr (CH₄/O₂/CO₂/N₂=3/1/1/4) 1 atm pressure and at 800 °C. Among the prepared catalysts Ni/Al₂O₃ gave the highest conversion and selectivity values. Besides, the lowest loss of activity was observed on Ni/Al₂O₃ catalyst as the flow rate increases.

GÜMÜŞ Ebru

Danışman : Doç. Dr. Tuncer YALÇINYUVA

Anabilim Dalı : Kimya Mühendisliği

Programı : Kimyasal Teknolojiler

Mezuniyet Yılı : 2014

Tez Savunma Jürisi : Doç. Dr. Tuncer YALÇINYUVA

Prof. Dr. Gülten GÜRDAĞ

Prof. Dr. Ahmet KAŞGÖZ

Doç. Dr. Ali DURMUŞ

Doç. Dr. Nihal YILMAZ ONUL