The theoretical part of the master's thesis describes the catalytic process of dry reforming, a process where biogas is converted into synthesis gas by means of a catalyst. This part of the paper describes the dry reforming process, lists the materials and method of preparation of the feed gas mixture, describes the composition and usefulness of the synthesis gas, describes the dry reforming reaction mechanism, an example of a fixed bed reactor system, lists some examples of useful catalysts, and the most important restrictions or obstacles to the implementation of the said procedure.
The production of the synthesis gas was studied using nickel catalysts, which were supported on cerium and zirconium oxide. Two different techniques (hydrothermal synthesis and synthesis with ethylene glycol) were used to prepare the support material. Calcined catalysts were characterized by BET analyses, H2-TPR, UV-Vis and XRD analysis. Cerium oxide has proven to be a good choice of support. The catalytic test showed the activity, selectivity and stability of the synthesized catalysts during the dry reforming of biogas within the reactor system with a solidified catalyst bed and an equimolar ratio of CH4 : CO2 feed mixture. The catalytic tests were performed in two ways, at stationary temperature and temperature programmed mode. Improved nickel catalyst stability was achieved using CeZrO2 mixed oxide. The degree of carbon deposition was determined by CHNS analysis.
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