The Anderson-type heteropolyanions in the synthesis of alumina-and zeolite-supported HDS oxidic precursors

摘要

This study is aimed at using and identifying Al- and Co-containing Anderson-type heteropolyanions in the synthesis of (Co)Mo/alumina and (Co)Mo/zeolite HDS catalysts oxidic precursors. Various techniques such as Raman spectroscopy, NMR and EXAFS are used to show the apparition of the AlMo_6O_(24)H_6~(3-) entity upon impregnation of an alumina or a zeolite with an ammonium heptamolybdate solution. The question of the Mo-Co interaction in the promoted precursors is also tackled through the use of the CoMo_6O_(24)H_6~(3-) entity.