New approach to the preparation of catalysts for the oxidative coupling of methane

作者：Vereshchagin S N^*; Kondratenko E V; Rabchevskii E V; Anshits N N; Solov' ev L A; Anshits A G

来源：Kinetics and Catalysis, 2012, 53(4): 449-455.

DOI：10.1134/S0023158412040131

A new approach to the preparation of systems that exhibit catalytic activity in the oxidative coupling of methane (OCM) is considered. With the use of ferrospheres separated from power-generation ashes from different sources as an example, it was demonstrated that OCM catalysts can be prepared by the crystallization/solidification of oxide melts with the formation of microspherical particles. The dependence of activity and selectivity for the oxidative reforming of methane on the ferrospheres containing from 36.2 to 92.5 wt % Fe2O3 into the products of deep oxidation and OCM was studied. It was found that deep oxidation reactions on ferrospheres with Fe2O3 contents higher than 85% were suppressed, and the main reaction path of CH4 conversion was its oxidative coupling with the formation of C-2 products (with selectivity to 60% at 750A degrees C); moreover, the selectivity for C-2 formation in this region was proportional to the concentration of Fe2O3. Phases responsible for the catalytic conversion of methane into CO (x) and OCM products were considered, and it was shown that the catalytic activity and selectivity of the oxidative transformation of CH4 on ferrospheres is determined by the position of the point that corresponds to their composition on a phase diagram of CaO-Fe2O3-SiO2.

• 出版日期2012-7