화학공학소재연구정보센터
Applied Catalysis B: Environmental, Vol.152, 152-161, 2014
The changing nature of the active site of Cu-Zn-Zr catalysts for the CO2 hydrogenation reaction to methanol
The effects of the most largely employed preparation methods (i.e., coprecipitation with sodium bicarbonate, complexation with citric acid, gel-oxalate coprecipitation) on the structure and catalytic behaviour of Cu-Zn-Zr systems for methanol synthesis from hydrogenation of carbon dioxide have been studied. The characterization data of the dried, calcined and reduced catalysts showed that the physico-chemical properties can be controlled by varying composition and preparation method. The catalyst obtained by the gel-coprecipitation procedure showed the highest catalytic activity in the T-R range 453-513 K, 3.0 MPa and 10,000h(-1), due to a superior functionality in the CO2 and H-2 activation. An adequate balance between metal and oxide surface sites, in correspondence of a well defined particle size, was proposed to be crucial to design active and selective catalysts for such reaction. The good performance of the gel-oxalate coprecipitated catalyst was confirmed by an endurance test (approximate to 200h), in which a constant and remarkable methanol space-time-yield value of 1200 g kg(cat)(-1) h(-1) at approximate to 10% CO2 conversion was obtained (T-R, 513 K; P-R, 3.0 MPa). (C) 2014 Elsevier B.V. All rights reserved.