Carriers support during drying

The results demonstrate that precursors, which do not easily crystallize, such as ammonium iron EDTA, ammonium iron citrate, and iron gluconate provide the best results. During drying, crystallization does not proceed readily the precursor can fairly completely cover the surface of the carrier with an amorphous layer. During calcination highly dispersed iron(III) oxide results. When the precursor crystallizes to small crystallites, micropores are generated that withdraw the solution from the pores of the support With wide-porous supports nucleation of small crystallites can easily lead to an inhomogeneous distribution of the precursor. 

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