3 research outputs found
One-Pot Transformation of Citronellal to Menthol Over H-Beta Zeolite Supported Ni Catalyst: Effect of Catalyst Support Acidity and Ni Loading
Citronellal was converted to menthol in a one-pot approach using H-Beta zeolite-based Ni catalyst in a batch reactor at 80 °C, under 20 bar of total pressure. The effects of H-Beta acidity (H-Beta-25 with the molar ratio SiO2/Al2O3 = 25 and H-Beta-300 with SiO2/Al2O3 = 300) and Ni loading (5, 10 and 15 wt %) on the catalytic performance were investigated. Ni was impregnated on H-Beta support using the evaporation-impregnation method. The physico-chemical properties of the catalysts were characterized by XRD, SEM, TEM, ICP-OES, N2 physisorption, TPR, and pyridine adsorptionâdesorption FTIR techniques. Activity and selectivity of catalysts were strongly affected by the BrĂžnsted and Lewis acid sites concentration and strength, Ni loading, its particle size and dispersion. A synergetic effect of appropriate acidity and suitable Ni loading in 15 wt.% Ni/H-Beta-25 catalyst led to the best performance giving 36% yield of menthols and 77% stereoselectivity to (±)-menthol isomer at 93% citronellal conversion. Moreover, the catalyst was successfully regenerated and reused giving similar activity, selectivity and stereoselectivity to the desired (±)-menthol isomer as the fresh one. Graphical Abstract: [Figure not available: see fulltext.
Corrigendum to âMicroreactor technology in experimental and modelling study of alcohol oxidation on nanogoldâ [Chem. Eng. Sci. 260 (2022) 117920](S0009250922005048)(10.1016/j.ces.2022.117920)
Introduction (page 1) âThe scenario dramatically changed as Haruta et al. (1985) and Hutchings (1987)â. SHOULD BE âThe scenario dramatically changed as Haruta et al. (1987) and Hutchings (1985)â. Notation [Table presented]SHOULD BE [Table presented] References The following references are missing in the reference list at the end of the article: Haruta, M., Kobayashi, T., Hiroshi, S., Nobumasa, Y., 1987. Novel Gold Catalysts for the Oxidation of Carbon Monoxide at a Temperature far below 0 °C. Chem. Lett. 16, 405â408. Hutchings, J.H., 1985. Vapor phase Hydroclorination of Acetylene: Correlation of Catalytic Activity of Supported Metal Chloride Syntesis. J. Catal. 96, 292â295