Preparation and characterization of Mo/HNa-Y zeolites

Intrazeolite nanocomposite catalysts: Co-Mo Sulfides for Hydrodesulfurization

“…The number of MdCO), molecules accommodated in each supercage (SC) was saturated at 1.9-2.1 Mo/SC or 12 wt. % Mo with respect to Nay, in agreement with the results by other workers (Komatsu et al, 1985;Yong and Howe, 1986). The HDS activities of MoSx/NaY and MoSJNaY are shown in Figure 1 as a function of the Mo content as expressed by Mo atoms/SC.…”

Structure of intrazeolite molybdenum oxide clusters and their catalysis of the oxidation of ethyl alcohol

“…After 12 h, the Mo content was saturated at 10 wt.% (2Mo/supercage) in line with the results of other workers. 10,15,24,27,28 When CVD-MoO 3 /NaY (10) was exposed again to Mo(CO) 6 vapor for 16 h, the Mo content increased to 13 wt.% Mo. Fig.…”

“…Many workers 10,11 have employed molybdenum hexacarbonyl Mo(CO) 6 encaged in cation exchanged zeolites to prepare Mo clusters with well-defined structure, such as Mo sulfide, [11][12][13][14][15][16][17][18][19][20][21][22] oxide, [23][24][25][26] oxy-carbide 27 and metal. 28 It was shown that the structure and size of the Mo sulfide clusters depend on the pore structure and composition of the host zeolite. 14,15,17 The preparation and structure of intrazeolite Mo oxide clusters have been studied by a variety of techniques including X-ray absorption fine structure (XAFS).…”

Preparation, Catalysis, and Characterization of Highly Dispersed Molybdenum Sulfide Catalysts Supported on a NaY Zeolite

“…Many fundamental researches have been, accordingly, conducted on molybdenum catalysts supported on zeolite both in oxidic and sulfided states. Molybdenum oxide precursors on zeolite are prepared by a variety of techniques; solid state reactions of MoCl 5 with hydroxyl groups in the cavities of H-form zeolites (Eugene and Lunsford, 1980;Johns and Howe, 1985;Howe et al, 1989), ion exchanges of zeolite extra framework cations with MoO 2 2+ (Howe et al, 1980;Minming and Howe, 1987;Howe and Minming, 1988;Ezzamarty et al, 1989), oxidation of Mo(CO) 6 encaged in zeolite (Komatsu et al, 1985;Ozin et al, 1992;Okamoto et al, 1993;Welters et al, 1994;Vorbeck et al, 1994), or most conventionally, impregnation of an aqueous solution of ammonium heptamolybdate (Cid et al, 1984;Cid et al, 1985;Lopez Agudo et al, 1986;Fierro et al, 1987;Corma et al, 1988;Leglise et al, 1988;Ezzamarty et al, 1989;Anderson et al, 1993a;Thoret et al, 1993;Kulbe et al, 1993;Welters et al, 1994). The last method usually accompanies calcination procedures in air at elevated temperatures to decompose the molybdenum compound.…”