Catalytic Decomposition of Methane in Fluidized Bed Reactor
Kaushal Parmar (Prof. K. K. Pant)
09th August 2017, Wednesday, 04:00‐04:30 pm (25+5 mins), ChE Seminar hall
The present work focuses on methane decomposition over 60%Ni-5%Cu-5%Zn/Al2O3 catalyst in a bubbling Fluidized Bed Reactor (FBR). Hydrogen production by thermocatalytic decomposition (TCD) of methane is a highly economical and environmentally attractive approach as compared to the energy intensive steam reforming reaction, which also produces 13.3 kg of CO2/kg of H2 produced. In TCD reaction, non-oxidative environment produces COx free hydrogen and carbon nanotubes. Carbon nanotubes (CNTs) produced during the reaction, accumulate on the catalyst and gradually deactivate the catalyst, which needs to be regenerated. A lab scale fluidized bed reactor with 12 mm ID with regeneration unit has been employed to overcome the difficulties of a fixed bed reactor. CNTs are separated from the catalyst by using the ultra-sonication method and the catalyst is regenerated. Incorporation of Cu and Zn improves the dispersion of the Nickel. Effect of methane partial pressure on methane conversion, time on stream hydrogen yield and CNT quality was studied. At methane partial pressure PCH4 = 0.25, more than 85% methane conversion was achieved. CNTs were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), and Raman Spectroscopy. Continuous deposition of CNTs on the catalyst particle changes the hydrodynamic behaviour from Geldart-A or B type to Geldart-C type.