Capacity oxygen absorption

Zirconium hydroxide is precipitated by bases at lower pH than the hafnium compound. Zr and Hf are obviously unable to form true hydroxides, and these compounds are more correctly formulated as MO2 XH2O. Amorphous hydrous zirconia and hafhia (a-phase) transform to microcrystalline forms (/f-phase) with noticeable heat evolution. They lose water up to the composition MO2 H2O at 140 °C (Zr) or 155 °C (Hf). Hydrous zirconia has excellent absorptive capacity, particularly for oxygen-containing anions. For example, the concentration of S04 anions over hydrous zirconia is so low that no precipitate forms on the addition of barium salts to the filtrate. While the hydroxides of composition M(OH)4 are not stable, in alkaline solutions, M(OH)s are present and even M(0H)6 anions have been reported in very concentrated alkalis. Salts of these anions, such as Na2Hf(OH)6, can be isolated. 

The catalyst is maintained at about 150 C to increase its oxygen absorption capacity (about 5x that at 25 C). 

High oxygen absorption capacity—so that it can rapidly transfer the oxygen from the bubble to the blood... 

Figure8 shows the experimental results of physical absorption of oxygen it is seen that sufficient carbon particles affect k, considerably.There seems to be no effect of other particles which have undoubtedly little adsorbing capacity and less porous structure then the activated carbon.Figure 9 shows the results of COp absorption experiments both for physical and chemical systems.

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