One-pot synthesis of ethylbenzene/1-phenylethanol and γ-butyrolactone from simultaneous acetophenone hydrogenation and 1,4-butanediol dehydrogenation over copper based catalysts: effects of the support

Abstract

The effect of the support in the simultaneous hydrogenation of acetophenone and dehydrogenation of 1,4-butanediol was studied using supported (MgO, g-Al 2 O 3 , MgO-Al 2 O 3 and SiO 2 ) copper (10 wt%) catalysts, prepared via impregnation. In this process, acetophenone was transformed to 1-phenylethanol/ ethylbenzene and 1,4-butanediol converted to g-butyrolactone/tetrahydrofuran under a hydrogen-free environment, indicating the major role of the supports. The Cu/MgO catalyst was active and highly selective towards the production of 1-phenylethanol and g-butyrolactone. However, an adverse behaviour was observed over Cu/MgO-Al 2 O 3 . An extraordinary catalytic performance was obtained over Cu/SiO 2 with high selectivity for ethylbenzene (99%) and g-butyrolactone (99%). Contrarily, no hydrogenation of acetophenone was observed over Cu/g-Al 2 O 3 due to the dehydration of 1,4-butanediol, yielding tetrahydrofuran. The main advantage of this process is that no external hydrogen is required for the hydrogenation of acetophenone. Copper dispersion, the reduction behaviour of copper, copper particle size and the acidity and basicity of the catalysts play important roles in the activity. All four catalysts were characterized using BET surface area, N 2 O pulse chemisorption, XRD, XRF, H 2 -TPR, XPS, and TPD of NH 3 /CO 2 to understand our results.

Realizing Catalytic Acetophenone Hydrodeoxygenation with Palladium-Equipped Porous Organic Polymers

“…3 AP hydrogenation is a complex multistep reaction with the competitive hydrogenation of the carbonyl group and aromatic ring and the concurrent hydrogenolysis of PhE, 4 and hence, all of these possible alternatives make it very challenging to selectively synthesize PhE/EB from AP. So far, several catalytic systems based on Pt, 5 Pd, 6 Ru, 7 and Cu 8 have been reported for this selective reaction. However, these catalytic systems present issues associated with harsh reaction conditions like high hydrogen pressures and high temperatures, as well as metal leaching, which are big hurdles for practical applications.…”

Lignosulfonate/Dicationic Ionic Liquid Composite as a Task-Specific Catalyst Support for Enabling Efficient Synthesis of Unsymmetrical 1,3-Diynes with A Low Substrate Ratio

“…XPS was employed to characterize the chemical states of elements on the surface of DIS@LS-TMEDA-Cu catalyst. The high-solution XPS spectra of Cu 2p in Figure a showed there was no characteristic Cu 2+ shakeup satellite peaks at 938–945 eV, suggesting that no Cu 2+ species existed in DIS@LS-TMEDA-Cu. − The lower BE peak at ∼929 eV could be ascribed to Cu + or Cu 0 species . Because it was difficult to differentiate Cu + and Cu 0 by Cu 2p 3/2 XPS spectrum, Auger Cu LMM spectra was further utilized.…”

Recent advances in fermentative production of C4 diols and their chemo-catalytic upgrading to high-value chemicals

“…However, new acidic sites were evolved by Mg doping, with lower 1,4-BDO conversion and GBL selectivity than Cu/SiO2. The effect of supports (MgO, -Al2O3, MgO-Al2O3, and SiO2) for 10 wt% Cu catalysts was evaluated for 1,4-BDO dehydrocyclization reaction [122]. While all other catalysts exhibited around 99% 1,4-BDO conversion, inferior catalytic activity was observed over Cu/MgO-Al2O3 due to poor metal dispersion.…”