Carbon monoxide removal, hydroxyl groups

Even more effective than carbon monoxide for removal of hydroxyl groups, was sulfur in the presence of carbon monoxide. Figure 3 also plots the hydroxyl population on silicas treated with C 2 vapor and carbon monoxide. The OH level separates from that of the air treated samples at as low as 400 C, and by 950 C very few hydroxyls remained. The exact mode of action of the sulfur in these experiments is unknown, but one possibility is that it somehow affects the water gas shift equilibrium. Sulfur was not detected on these samples. 

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