Atomically Dispersed Rh Active Sites on Oxide Supports with Controlled Acidity for Gas-Phase Halide-Free Methanol Carbonylation to Acetic Acid

Gas-phase methanol carbonylation over HMOR catalyst was investigated for the synthesis of dimethyl ether (DME) and acetic acid (HOAc). The results revealed that the selectivity of DME reached 98% and the methanol conversion was 45% under the reaction temperature of 493K. While, the selectivity of HOAc was 30% and the methanol conversion reached 80% when reaction temperature was increased to 573K. TEM, SEM, XRD, N2 physisorbtion, XPS and TG-DTG measurements were performed to characterize the texture and structure of the catalyst. Serious coking on the catalyst surface significantly limited the utilization of unmodified HMOR catalyst in the reaction.

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Revisiting Glycerol Esterification with Acetic Acid over Amberlyst-35 via Statistically Designed Experiments: Overcoming Transport Limitations

10.26434/chemrxiv.7731305.v1 ◽

2019 ◽

Author(s):

Víctor Gabriel Baldovino Medrano ◽

Karen V. Caballero ◽

Hernando Guerrero-Amaya

Keyword(s):

Acetic Acid ◽

Active Sites ◽

Batch Reactor ◽

Catalyst Particle ◽

Experimental Designs ◽

Particle Sizes ◽

Turnover Rates ◽

Designed Experiments ◽

Different Temperatures ◽

Glycerol Esterification

Turnover rates for glycerol esterification with acetic acid over Amberlyst-35 were measured under different temperatures, reactants and active sites concentrations, and catalyst particle sizes. Data were collected in a batch reactor. Experiments were done following a sequence of factorial experimental designs.

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Study of deactivation in mesocellular foam carbon (MCF-C) catalyst used in gas-phase dehydrogenation of ethanol

Scientific Reports ◽

10.1038/s41598-021-91190-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoottapong Klinthongchai ◽

Seeroong Prichanont ◽

Piyasan Praserthdam ◽

Bunjerd Jongsomjit

Keyword(s):

Catalytic Activity ◽

Pore Size ◽

Gas Phase ◽

Surface Area ◽

Active Sites ◽

Operating Temperature ◽

Coke Formation ◽

Ethanol Conversion ◽

Deactivation Of Catalyst ◽

Dehydrogenation Of Ethanol

AbstractMesocellular foam carbon (MCF-C) is one the captivating materials for using in gas phase dehydrogenation of ethanol. Extraordinary, enlarge pore size, high surface area, high acidity, and spherical shape with interconnected pore for high diffusion. In contrary, the occurrence of the coke is a majority causes for inhibiting the active sites on catalyst surface. Thus, this study aims to investigate the occurrence of the coke to optimize the higher catalytic activity, and also to avoid the coke formation. The MCF-C was synthesized and investigated using various techniques. MCF-C was spent in gas-phase dehydrogenation of ethanol under mild conditions. The deactivation of catalyst was investigated toward different conditions. Effects of reaction condition including different reaction temperatures of 300, 350, and 400 °C on the deactivation behaviors were determined. The results indicated that the operating temperature at 400 °C significantly retained the lowest change of ethanol conversion, which favored in the higher temperature. After running reaction, the physical properties as pore size, surface area, and pore volume of spent catalysts were decreased owing to the coke formation, which possibly blocked the pore that directly affected to the difficult diffusion of reactant and caused to be lower in catalytic activity. Furthermore, a slight decrease in either acidity or basicity was observed owing to consumption of reactant at surface of catalyst or chemical change on surface caused by coke formation. Therefore, it can remarkably choose the suitable operating temperature to avoid deactivation of catalyst, and then optimize the ethanol conversion or yield of acetaldehyde.

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Determination of Acetic Acid in Vinegar by Gas Phase Molecular Absorption Spectrometry After Methyl Acetate Generation

Microchimica Acta ◽

10.1007/s006040050067 ◽

2000 ◽

Vol 134 (3-4) ◽

pp. 199-203 ◽

Cited By ~ 1

Author(s):

Isabel Sanz-Vicente ◽

Susana Cabredo ◽

Javier Galban

Keyword(s):

Acetic Acid ◽

Gas Phase ◽

Methyl Acetate ◽

Absorption Spectrometry ◽

Molecular Absorption ◽

Molecular Absorption Spectrometry

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Laser electrodispersion as a new chlorine-free method for the production of highly effective metal-containing supported catalysts

Pure and Applied Chemistry ◽

10.1351/pac-con-11-07-12 ◽

2012 ◽

Vol 84 (3) ◽

pp. 495-508 ◽

Cited By ~ 23

Author(s):

Ekaterina S. Lokteva ◽

Anton A. Peristyy ◽

Natalia E. Kavalerskaya ◽

Elena V. Golubina ◽

Lada V. Yashina ◽

...

Keyword(s):

Gas Phase ◽

High Stability ◽

Heterogeneous Catalysts ◽

Supported Catalysts ◽

Promising Technique ◽

Wet Impregnation ◽

Oxide Supports ◽

Highly Active ◽

Specific Catalytic Activity ◽

Free Metal

Laser electrodispersion (LED) of metals is a promising technique for the preparation of heterogeneous catalysts as an alternative to wet impregnation of supports with the corresponding salt solutions. The LED technique can be used to deposit highly active chloride- and nitrate-free metal nanoparticles onto carbon or oxide supports. We report preparation and properties of new Ni-, Pd-, and Au-containing alumina-supported catalysts with low metal loadings (10–3–10–4 % mass) and their comparison with the previously studied carbon (Sibunit) supported systems. The catalysts demonstrate high stability and extremely high specific catalytic activity (by 2–3 orders of magnitude higher than for traditional catalysts) in the gas-phase hydrodechlorination (HDC) of chlorobenzene (CB).

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Abraham model correlations for estimating solute transfer of neutral molecules into anhydrous acetic acid from water and from the gas phase

Journal of Molecular Liquids ◽

10.1016/j.molliq.2015.08.042 ◽

2015 ◽

Vol 212 ◽

pp. 16-22 ◽

Cited By ~ 8

Author(s):

Dawn M. Stovall ◽

Amber Schmidt ◽

Colleen Dai ◽

Shoshana Zhang ◽

William E. Acree ◽

...

Keyword(s):

Acetic Acid ◽

Gas Phase ◽

Solute Transfer ◽

Abraham Model ◽

Anhydrous Acetic Acid

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Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions

Journal of Chemistry ◽

10.1155/2018/7037461 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Ali Alsalme ◽

Aliyah A. Alsharif ◽

Hamda Al-Enizi ◽

Mujeeb Khan ◽

Saad G. Alshammari ◽

...

Keyword(s):

Acetic Acid ◽

Active Sites ◽

Catalyst Support ◽

Supported Catalyst ◽

Catalytic Efficiency ◽

Biodiesel Production ◽

Effect Of Temperature ◽

Heteropoly Acids ◽

Catalyst Loading ◽

Esterification Activity

Supported heteropoly acids are an interesting class of solid acid catalysts which possess flexible structure and super acidic properties essentially required for the oil-based biodiesel production. In this study, a series of catalysts containing 25 wt.% of heteropolytungstate (HPW) supported on various clays or SiO2 were prepared, and their catalytic efficiency was evaluated for esterification of acetic acid with heptanol. The as-prepared catalysts were characterized by various techniques including FT-IR spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and BET. The catalytic efficiency of both bulk and supported HPW catalysts for the esterification activity strongly depends on the type of support and amount of catalyst; the bulk HPW catalyst and the catalyst supported by kaolinite with 25 wt.% of HPW exhibited highest activity. In order to study the effect of temperature on conversion, all the catalysts were subjected to different reaction temperatures. It was revealed that esterification activity of both bulk and supported HPW catalysts strongly depends upon the temperature variations of the reaction. Besides, the effect of leaching of active sites on the catalysts performance for biodiesel production was also evaluated by inductively coupled plasma studies (ICP). The kaolinite-supported catalyst (25% HPW/kaolinite) demonstrated higher amount of leaching which is also confirmed by the significant decrease in its catalytic activity when it is used for the second time. However, the higher activity demonstrated by HPW/kaolinite maybe because of some homogeneous reaction indicating a weak catalyst support interaction (WCSI) resulting in the leaching of the catalyst during the test. Furthermore, the effects of other reaction variables such as catalyst loading and reaction time on the conversion of acetic acid were also studied.

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