III International Conference

PP-II-128enhanced stability against carbonization in comparison with the granulated catalysts which iscaused by maintenance of necessary balance between rates of СН 4 decomposition on metalnickel and СО 2 dissociation on border metal - oxide as it was reported in work [3].To prepare the structured Cu-ZnO catalysts for methanol reforming, samples of thecordierite monoliths, initially coated with γ-Al 2 O 3 , were impregnated with solutions of zincsulfate and copper nitrate followed by calcination and reduction.As shown from the Table, granulated commercial (a sample 1) and structured (a sample2) catalysts with nearly identical contents of an active component (about 8 % NiO) practicallydo not differ with respect to activity (temperature of 80 % conversion) while decrease of NiOcontent to 4,0 % (a sample 3) results only in insufficient decrease of the catalyst activity.However, productivity of the monolithic catalyst is almost four times higher as compared withgranulated one. Moreover, productivities of the structured and granulated catalysts per aweight unit of nickel oxide, differ even more considerably (since in catalysts of honeycombstructure a wall thickness of the monolith is commensurate with depth of a working layer and,therefore, a higher degree of an active component’s use is achieved).Table. Activity and productivity of catalysts in CO 2 methane conversion№TemperatureProductivityCatalystof 80 % conversion, А . 10 6 , B . 10 6 ,°Сmol·s -1·g -1cat mol·s -1·g -1NiO1 GIAP-18 (commercial) 485 12,96 1,6228,2wt.% NiO/11,2wt.%Al 2 O 3 /cordierite480 38,3 4,83 4,0wt.% NiO/11,2wt.% Al 2 O 3 /cordierite488 32,0 7,2When using Cu-ZnO/γ-Al 2 O 3 -based monoliths (with no more than 15 wt. % of (Cu +ZnO) loadings) in partial oxidation and steam reforming of methanol, formation of hydrogenwith a yield about 80 % and, respectively, 90 % was observed.Thus, use of honeycomb structure catalysts on ceramic monoliths enables to reduceessentially the content of active components in catalyst compositions of CO 2 conversion ofmethane, oxygen and steam reforming of methanol without decrease in their productivity.References1. J.H.Lunsford. Catal. Today. 63, 2000, P.165.2. B.Lindström, L.J.Petterson. J.Power Sources. 106, 2002, P.264.3. B.-Q. Xu, J.-M. Wei, Y.-T. Yu, Y.Li, J.-L. Li, Q.-M. Zhu. J. Phys. Chem. B. 107, 2003, P.5203.399