Activated carbons shortcomings

For the ruthenium catalyst supported on activation carbon, the methanation reaction of the carbon support can also be catalyzed by ruthenium. This is another shortcoming of ruthenium catalyst which results in the loss of carbon support and impact on the catalyst lifetime. However, researchers have found that methanation reaction occurs at higher temperatures than ammonia synthesis reaction, so that the loss of carbon via methanation might be avoided when the reaction is performed at relatively low temperatures. 

AX21, a result that quenched the enthusiasm of the earlier report. Coke formation from styrene polymerization was recognized as one of the shortcomings of the reaction, leading to micropore plugging. No direct relationship could be found between the activity and the surface area of the carbon materials, and it was observed that the most active catalysts were those with more mesopores and higher external surface area. 

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