Structural Characterization of Carbons Derived from Methane Pyrolysis
Research output: Thesis › Master's Thesis
The world is currently facing the enormous task of massively reducing the carbon dioxide emissions for energy production within the next decades. Switching to hydrogen as an energy carrier is a possible approach for a sustainable and climate-neutral energy production. Hydrogen may be produced without carbon dioxide emissions by means of methane pyrolysis which yields large quantities of carbon as a complementary product. To allow a large-scale application of methane pyrolysis, this carbon must be put to use. In this thesis, carbons derived from three different laboratory-scaled methane pyrolysis processes were investigated using advanced characterization techniques including X-ray diffraction, small-angle X-ray scattering, gas sorption analysis, thermogravimetric analysis, and Raman spectroscopy. The carbon phase derived from a liquid metal process utilizing a catalyst of Cu and Ni was reported to be turbostratic carbon. The plasma process yielded a mixture of graphite and turbostratic carbon with a BET area of up to 75.8 m²/g. Graphite was reported from a fixed bed process using reduced iron ore as a catalyst. Contrary to multiple literature studies no other allotropic forms of carbons were detected, such as graphene, carbon nanotubes or carbon fibers. All carbons contained significant amounts of impurities in a range between 31.4 wt% and 89.7 wt%. Carbon purity must be increased in future studies for the carbon product to be marketable. Many potential high-tech applications of carbon require a nanoporous structure combined with a large specific surface area. This may be achieved in a subsequent activation step and should be investigated in future research.
|Translated title of the contribution||Strukturcharakterisierung von Kohlenstoffen aus der Methanpyrolyse|
|Publication status||Published - 2021|