Silica-Alumina-Supported Acidic Molybdenum Catalysts - TPR and XRD Characterization

Preparation, characterization, and catalytic activity of CoMo/γ-Al2O3 catalysts prepared by equilibrium deposition filtration and conventional impregnation techniques

“…Two main peaks appear at ca. 500 and 900 • C, which are typical of well-dispersed molybdenum supported species [35][36][37][38][39][40][41][42][43][44][45]. The absence of any TPR peak at 350 • C corresponding to the bulk cobalt oxide [19,46] provides additional proof that the Co octahedral species, detected by DRS, are very well dispersed, in agreement with the LRS results mentioned above.…”

Metathesis of ethylene and butylene-2 to propylene with Mo on Hβ-Al2O3 catalysts

“…According to Refs. [7,8], the l, m and h peaks correspond to the reduction of polymolybdate or multilayered Mo oxide to MoO 2 , Al 2 (MoO 4 ) 3 and microcrystalline MoO 3 to MoO 2 , and MoO 2 to Mo, respectively. As shown in Fig.…”

Study on the NaNp/Al2O3–SiO2 system

“…The alumina-silica gels of specific composition examined in the study were obtained by modification of the method described by Miranda and co-workers [2]. Instead of a separate formation of a silica sol by hydrolysis from Na 2 SiO 3 and of aluminum hydroxide sol from Al(NO 3 ) 3 , the sols were precipitated from an aqueous mixture containing sodium silicate and aluminum nitrate in suitable concentration by adding NH 4 NO 3 or NH 4 OH to obtain a pH 8 mixture.…”

“…Amorphous alumina-silica gels Al 2 O 3 -SiO 2 are recognized as both catalysts and supports for catalytic active phases of metals and their compounds, such as oxides, sulfides, or organometallic complexes [1][2][3]. Usually the catalytic and physicochemical properties of these gels vary continuously with the varying content of their components.…”