Investigation into the effect of the intermediate carbon carrier on the catalytic activity of the HDS catalysts prepared using heteropolycompounds

Evolution and interlayer dynamics of active sites of promoted transition metal sulfide catalysts under hydrodesulfurization conditions

“…The ammonium salts of 6-molybdonickelate (NH 4 ) 4 [Ni(OH) 6 heteropolyacids were synthesized in accordance with published procedures [37][38][39]. To confirm the structure of the heteropolycompounds, their IR spectra were recorded and phase composition was determined.…”

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

“…During sulfidation the cobalt citrate is destroyed with migration of cobalt atoms to the edges of multilayer slabs of CoMoS phase in statu nascendi and partially to formation of separated cobalt sulfide, such as Co 9 S 8 , and besides, small amount of coke up to 1.5 wt.% (Table 1) are obtained from citrate molecules. In [13] we have already shown that the use of intermediate carbon carrier placed between alumina and active phase allowed to increase the stacking number of active phase and catalysts activity. Recently, other authors have indicated [47,59,60] the carbon residual species formation, when chelating agents or organic additives were used in catalysts preparation.…”

“…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.…”

“…The main advantage of HPCs of Anderson type is the presence of a 3d-metal (Ni and Co including) as a heteroatom in heteropolyanion (HPA) [9,13,15,18,19]. Such metal plays the role of a promoter in the formation of the catalyst active phase and its nature is extremely important for catalytic activity.…”

Ni–W2C/mpg–C3N4 as a promising catalyst for selective hydrogenation of nitroarenes to corresponding aryl amines in the presence of Lewis acid

“…To develop highly efficient and highly selective catalytic systems for aryl amine production under relatively low reaction and presure is highly desirable, but it still remains challenge. mpg-C 3 N 4 materials with two-dimension pore architecture possess higher specific surface area and larger pore volume, which results in enhanced catalytic performances in catalysis due to higher surface density of active sites exposed on the surface, their easier accessibility by strengthened diffusion, and the basicity [14,15,[29][30][31][32][33][34][35][36][37]. Hopefully the offered base sites from mpg-C 3 N 4 may strengthen the synergistic effect between the supported Ni-W 2 C catalyst and Lewis acid that was established in our previous report [10].…”