Use of the cobalt salt of the heteropolyanion [Co2Mo10O38H4]6− for the preparation of CoMo HDS catalysts supported on Al2O3, TiO2 and ZrO2

Preparation of new oxidic precursors based on heteropolyanions for efficient hydrocracking catalysts

“…These results show that the average length and stacking of the HPA based catalysts were higher than those obtained for the conventional ones. However, whatever the material is, the average length (between 14.6 and 20.8 Å ) is smaller than values reported for WS 2 on ASA support [13] and for MoS 2 supported phase [14]. As shown in Fig.…”

Effect of Co on HDS Activity of Alumina-supported Heteropolymolybdate

“…The catalysts showed a distinct maximum in catalyst activity (thiophene conversion 45%) located at molar ratio Co/Mo = 0.27. Over the catalyst CZA3 having lower concentration of Mo [39] thiophene HDS reaction is not sensitive to the stacking of MoS 2 slabs. Therefore, we can speculate that a slightly better performance of the catalyst with higher Mo loading is the consequence of a larger concentration of the oxymolybdenum phase observed after calcination.…”

CoMo/Al2O3 catalysts prepared on the basis of Co2Mo10-heteropolyacid and cobalt citrate: Effect of Co/Mo ratio

“…The proximity of cobalt and molybdenum atoms in starting material has been considered by Van Veen [24] as a criterion for obtaining good promoting effects of the Co atoms. The use of HPAs with higher Co/Mo ratio leads to raising the promoting effect of the cobalt in the HDS of thiophene [9,13,16,20,21]. However, a HPA, in which Co/Mo ratio is equal to 0.5, has not been found yet.…”

“…However, a HPA, in which Co/Mo ratio is equal to 0.5, has not been found yet. It has been established [10][11][12]14,20,21] that catalysts prepared on the basis of Co(Ni) salts of HPAs are more effective than ones synthesized from ammonium salts or by conventional methods from AHM with cobalt nitrate. Because of different reactivity, sulfidation mechanism of Co 2+ cations in cobalt salt of [Co 2 Mo 10 O 38 H 4 ] 6À (Co 3 ACo 2 Mo 10 HPA) may be distinguished from Co 3+ placed into Co 2 Mo 10 HPA.…”