Specific surface area absorbate influence

However, a certain fraction of the active material reacts with the surface phosphate groups of the support to inactive iron phosphate and molybdenum phosphate. The amount of metal phosphate depends on the specific surface area of the support and the surface concentration of phosphate groups. Both are influenced by the pH of precipitation of the support and by the Al/P ratio in the initial Al3+ and P04 solution. Although the formation of metal phosphate decreases the capacity of the absorbent towards the removal of H2S, the strong interaction with the support ensures a high thermal stability. 

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