Catalytic behavior of Pd/SiO2 catalysts prepared using water-in-oil microemulsion in CO hydrogenation

catalytic behavior of Pd/SiO2 catalysts prepared using water-in-oil (w/o) m icroemulsion has been studied in comparison with that of the impregnated Pd /SiO2 catalysts in CO hydrogenation. In the case of Pd/SiO2 catalyst prepar ed using w/o microemulsion, the CO conversion increased with time-on-stream and showed a very high constant value after 40 h. The selectivity to the o xygenates with more than one carbon (C2+) also increased with time and achi eved an extremely high value when the CO conversion was constant. The extre mely high CO conversion and C2+ oxygenate selectivity of the catalyst prepa red using w/o microemulsion was considered to be due to the coexistence of Pd with different oxidation states.