Self-propagating high-temperature synthesis (SHS) method is used worldwide for the low-cost production of engineering and functional materials such as advanced ceramics, intermetallics, catalysts and magnetic materials. The method exploits self-sustaining solid-flame combustion reactions for the internal development of very high temperatures over very short periods. It therefore offers many advantages over traditional methods such as much lower energy costs, ease of manufacture and capability for producing materials with unique properties and characteristics. It was found, that method offers a good possibility for the preparation of new, active ceramic catalysts and carriers with compositions, structure and properties, which satisfy the stringent requirements of many applications. Very high interest to SHS catalysts can be explained by high activity of catalysts prepared by this methods and advantages of SHS method in comparison with traditional methods of preparation.
Resistant to temperature extremes and thermal shocks is one of the most important requirements for catalysts. Works on research of intermetallic compounds as a contact mass for conversion of methane were carried out. Method of self-propagating high temperature synthesis was used for synthesis of catalysts. Investigation of the activity of catalysts based on the initial mixture of metal oxides with the addition of waste slag from metallurgical production produced by solution combustion synthesis process was carried out in the reaction of carbon dioxide conversion and partial oxidation of methane. The catalysts were prepared by SHS and incipient wetness supporting methods based on Ni-Cr-Al-Mg system. The analyses of Ni-Cr-Al-Mg catalyst using XRD, SEM and BET methods provided useful information in understanding the catalytic activity of catalysts at the conversion of methane. It was found causes of optimal catalyst activity. The increase of NiO concentration and decrease of the Al concentration in the initial charge increases combustion velocity. It is connected with approach the stoichiometric composition, and therefore a greater heat generation affects the increase in the reaction rate. High temperatures (when there is more than 27% NiO and lower than 55% Al in the initial batch) affect the stabilization of the crystal lattice. The change of crystal lattice parameters influences the catalytic activity. 99% methane conversion at 900°C was carried out on the catalyst, as well as the conversion of CO2 reached 98% at 900oC. H2 yield reached 40%, yield of CO - 60% in the ratio of H2/CO = 1.5-1.7. Thus, effective catalysts for the production of synthesis gas from methane have been developed. These data indicate a significant advantage of the new composite materials produced by combustion synthesis process.
This research was funded by Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (grant number AP08855562, AP08052090).
|Publication||Impact Factor journals|
|Affiliation of speaker||D.V. Sokolsky Institute of Fuel, Catalysis and Electrochemistry|
|Position of speaker||Prof.|