Contribution to MoO3–SiO2 and WO3–SiO2 utilization—active catalysts in jasmine aldehyde, 2-hexyl-1,3-dioxolane and methyllaurate synthesis

Solvent Influence on Selectivity in α-Pinene Oxide Isomerization Using MoO3-Modified Zeolite BETA

“…Materials were prepared by wet impregnation from zeolite BETA (Si/Al = 38, CP814C, Zeolyst Int., Kansas city, KS, USA) and ammonium heptamolybdate tetrahydrate (Chemapol, Praha, Czech Republic, >99.5%). Two different wet impregnation processes were used: impregnation at room temperature [25,26,42] and at 60 • C [14]. To prepare the material with the desired Mo amount 20 wt.% 6.4 g of molybdate and 10 g of zeolite BETA was used.…”

“…Several types of Mo-modified materials were prepared by wet impregnation method of BETA38 zeolite. The wet impregnation method is commonly used for zeolite modification and was performed using two temperatures based on the literature data: 60 • C [10,14] (for materials 20Mo450, 20Mo500, 20Mo550, 20Mo600) and RT (20Mo450RT) [25,26]. The effect of calcination temperature on the material properties and catalytic activity was also tested-calcination temperatures 450, 500, 550 and 600 • C (used calcination temperature is contained in materials name-e.g., 20Mo550 was calcined at 550 • C).…”

“…Alcohols reacted with APO forming products with higher MW; it is likely that addition on a C-C double bond or oxirane ring-opening occurred. Nitromethane behaved differently probably (Table 4) because either by its different structure or by the fact that both its dielectric constant (35.9 vs. 15-21.8) and its donor number (2.7 vs. [19][20][21][22][23][24][25] are far different from dielectric constants and donor numbers of aforementioned alcohols. Using noncyclic alcohol, the total conversion of APO was obtained in the first 5 minutes of reaction.…”

“…Molybdenum modified materials are active acid catalysts (because of material Lewis acidity enhancement due MoO3 content [25,26]) and may serve as catalysts in alkane isomerization [27][28][29][30][31]. Usage of molybdenum-based catalyst in α-pinene oxide is also reported [32].…”

Study of the characteristics and properties of the SiO2/TiO2/Nb2O5 material obtained by the sol–gel process

“…Besides this, these materials combine the mechanical properties of the silica matrix with the chemical properties of the metal oxides, exhibiting different chemical and physical properties from those observed in the oxide alone, especially because the presence of Brønsted and Lewis acid sites on the oxide mixture 3 , 4 , 11 – 14 . Hence, the oxides mixture are interesting materials for various applications 3 , 4 : as heterogeneous catalysis 2 , 9 , 15 , 16 , photoanodes for solar cells 6 , photocatalytic activity 7 , optical properties 8 , bioactive glass 10 , preconcentration systems of metallic ions 11 , 17 – 19 , dye remediation or adsorbent in aqueous solution 5 , 20 , adsorption of interest molecules 21 , development of new chemically modified electrodes 22 , 23 , among others.…”