The addition of barium, as a secondary promoter, to alumina-supported Ni-Mo
(nickel oxide-molybdenum oxide) catalyst was investigated. The results of
thiophene hydrodesulfurization experiments carried out on the catalysts sho
w that the addition of small amounts of barium (<0.7 wt%) leads to a signif
icant improvement in their thiophene hydrodesulfurization. Experiments carr
ied out in an autoclave also show that the presence of barium leads to impr
ovement in the properties of the products obtained after gas oil processing
. These results may help in developing catalysts with improved activities,
as only a small amount of barium secondary promoter is required.