Zr- and La-containing Catalysts in Synthesis of Methanol and Dimethyl Ether

• Published in: Russian journal of applied chemistry 2019-08, Vol.92 (8), p.1084-1093, Article 1084
• Main Authors: Kipnis, M. A., Kosolapova, A. P., Belostotskii, I. A., Volnina, E. A., Bondarenko, G. N., Levin, I. S., Ponomarev, A. B.
• Format: Article
• Language: English
• Subjects: Adsorption; Aluminum oxide; Catalysis; Catalysts; Chemical synthesis; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Dehydration; Dimethyl ether; Heat treatment; High temperature; Industrial Chemistry/Chemical Engineering; Infrared spectroscopy; Methanol; Silicon dioxide; Surface chemistry; Transitional aluminas; Tungsten oxides; Zirconium dioxide; Zirconium oxides
• ISSN: 1070-4272; 1608-3296; 1608-3296
• DOI: 10.1134/S1070427219080056

Zirconium oxide samples synthesized and modified with Al, Si, W oxides were studied as dehydrating components of bifunctional catalysts for synthesis of dimethyl ether. ZrO 2 modified with Al and Si oxides is inactive in the dehydration of methanol, but its dehydrating activity becomes comparable with the activity of γ -Al 2 O 3 upon introduction of WO 3 . According to the data on methanol adsorption at 46°C, the adsorption capacity of ZrO 2 modified with SiO 2 is comparable with the capacity of γ -Al 2 O 3 , and that of ZrO 2 modified with WO 3 is four times lower. The difference in the catalytic and adsorption behavior of the samples is accounted for by the data of in situ high-temperature diffuse reflection IR spectroscopy. A high content of weak Brønsted acid centers is observed on the ZrO 2 surface, with the interaction of these with methanol resulting in the methoxylation of the catalyst surface. When W oxide is deposited onto zirconium oxide, the surface has strong Brønsted centers involved in the reaction of methanol dehydration. A coprecipitation from solution of nitrate salts of Cu, Zn, La with Na carbonate, followed by the procedures of filtration, washing, and thermal treatment, yielded a catalyst for synthesis of methanol, the activity of which is close to that of the industrial catalyst.