Recent advance in catalysis for solving CO_2 problems was summarized. For these purposes, an ultra-rapid reforming of metane to syngas with a space-time yield (STY) of 25,000 mol/l-h was achieved by using a Rh-modified Ni-Ce_2O_3-Pt catalyst, in which the Rh part played a role of portholes for hydrogen spillover and prevented the coke deposit on the catalyst surface. Ultra-rapid methanation of CO_2 was also achieved by using a Ni-La_2O_3-Ru catalyst supported on the spherical silica particles having a meso-macro bimodal pore structure. A new catalyst composed of Cu-Zn-Cr-Al-Ga oxides modified with a supported Pd exerted a high activity with a high STY of methanol, 6,700 g/l centre dot h. The catalyst components, Pd and Ga controlled the reduction state of the catalyst surface by their roles of normal and inverse spillover of hydrogen, respectively. Ethanol was effectively synthesized by CO_2 hydrogenation using bi-functional composite oxide catalysts having carbon-carbon growth property and OH group insertion property. Methanol was totally converted on the metallosilicate catalysts containing Ga or Fe into aroma-poor gasoline selectively with a STY of 1,860 g/l centre dot h and 328 g/l centre dot h from CO-rich syngas and CO_2-rich syngas, respectively. When SAPO-34 catalyst was used for methanol conversion, ethylene and propylene were produced almost exclusively with an equivalent ratio. These effective conversion of CO_2 to valuable compounds have a high potetial to mitigate CO_2 accumulation and recycle use of CO_2.
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