Effect of reduction temperature on interaction and sintering

The reduction temperature influences the metal-support interaction and agglomeration, which occurs frequently on supported catalysts and will be illustrated for the nickel supported catalyst. It depends on the support, the metal concentration, the calcination temperature, the reducing agent, the H2 concentration, and water. When promoted with potassium, lanthanum or any other promoter improves the reduc-ibility and the metal distribution. After calcination, nickel is an oxide, but can also be Ni203, as suboxide, or as aluminate [17]  

The reduction of nickel oxide after calcination occurs as follows NiO-l-Hi Ni -l-HiO AH = 0.4 kcal / moles 

If the reduction is direct of the precursor nitrate, then the following reactions may occur  

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