The influencing factors during impregnation

Catalyst No Loading order CO uptake/ (cm -g i) Ru dispersion/% Ru surface area/(m -g ) Ru grain size/nm Activity (v/v)% 425°C 400°C  

It is seen from Table 6.20 that different solvents have great effect on the loading effect of the active components. The dispersion of ruthenium is the highest when H2O is used as solvent, while with THF as solvent, the dispersion of ruthenium is the lowest and the catalytic activity is the worst. However, a lot of researchers considered that the effect of the acetones is better than that of the H2O, which is related probably with the surface characters of the activated carbons, especially the hydrophilicity. The surface of the ordinary activated carbons is hydrophobicity. 

Solvent Uptake of CO/ (cmUg-i) Dispersion of Ru/% Surface area of Ru/(m g ) Grain size of Ru/nm 

It is seen from Fig. 6.34, based on the results by scanning electron microscopy that part of ruthenium particles show aggregated status, large size and distributed unevenly when impregnation time is 3 h and 6 h, respectively. It can be seen from Fig. 6.34(c) that when impregnation time is 18 h, ruthenium is evenly distributed over surface of activated carbon and the pore orifice of support which is very clearly eyeable without obvious blocked objects. 

4 Reduction of RuCls XH2O and elimination of chlorine ions 

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