SBA-15 mesoporous molecular sieve as an appropriate support for highly active HDS catalysts prepared using Mo and W heteropolyacids

SBA-15 Mesoporous Silica as Catalytic Support for Hydrodesulfurization Catalysts—Review

“…Concerning the SBA-15-supported transition metal sulfide catalysts prepared by sulfidation of oxide precursors, with the exception of CrRu/SBA-15 [35] and RuS 2 /Zr-SBA-15 [45], the optimization and testing of Mo/SBA-15 and W/SBA-15 sulfide catalysts in HDS reactions is mainly reported [65,72,73,74,75,76,77,78,79,80,81,82]. The latter catalysts are obtained by sulfidation of their oxide catalyst precursors with a 10% H 2 S/H 2 gas mixture at 400 °C (Mo/SBA-15) or 450 °C (W/SBA-15) for 4–6 h. The temperature necessary for sulfidation of W-based catalysts is higher than those needed for their Mo-based counterparts, because the WO 3 convers much slower to WS 2 than MoO 3 does to MoS 2 .…”

“…Lizama et al [ 79 ] reported the effect of heteropoly-acids (H 3 PW 12 O 40 and H 3 PMo 12 O 40 ) as active phase precursors together with the effect of different promoters (Co against Ni) loaded on Mo(W)/SBA-15 catalysts on the performance HDS of 4,6-DMDBT. The catalyst characterization results demonstrated that the SBA-15-supported heteropoly-acids were well dispersed and maintained their characteristic Keggin structure once calcined at 350 °C for 2 h. Contrary to Co, the use of Ni as promoter led to a significant decrease in the temperature of the reduction of metal oxide species.…”

“…Both Ni-promoted Mo/SBA-15 and W/SBA-15 catalysts showed high activity in the 4,6-DMDBT HDS reaction, which was substantially higher than that of the NiMo/Al 2 O 3 reference sample. From these results, it was concluded that SBA-15 is a good substrate, and the heteropoly-acids as active phase precursors are promising for the preparation of novel Ni–Mo and Ni–W HDS catalysts [ 79 ].…”

“…Contrary to the transition metal sulfides [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 ], studies on the use of SBA-15 substrate for supporting non-noble metal phosphides are not numerous [ 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 ]. In general, non-noble metal phosphides, such as Co, Ni, Mo or W, exhibited higher HDS activity than their sulfided counterparts [ 5 ].…”

“…During the last two decades, various mesoporous structures have been synthesized, which can be roughly classified into three categories based on the pore types: nearly spherical cage, cylindrical channel and bi-continuous channel [19]. Among different ordered mesoporous silicas, SBA-type silicas are the most frequently studied [13,14,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,…”