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Keras
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Quote: Originally posted by clearly_not_atara |
Unfortunately the only paper I found about this acid is in French, although the lithium salt is well-described. Apparently LiBOB forms a monohydrate?
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Lol, I am French, so thanks for that :p
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leau
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Diethyl Ether Production during Catalytic Dehydration of Ethanol over Ru- and Pt- modified H-beta Zeolite Catalysts
Tanutporn Kamsuwan, Piyasan Praserthdam, Bunjerd Jongsomjit
J Oleo Sci. 2017;66(2):199-207.
doi: 10.5650/jos.ess16108.
In the present study, the catalytic dehydration of ethanol over H-beta zeolite (HBZ) catalyst with ruthenium (Ru-HBZ) and platinum (Pt-HBZ)
modification was investigated. Upon the reaction temperature between 200 and 400°C, it revealed that ethanol conversion and ethylene selectivity
increased with increasing temperature for both Ru and Pt modification. At lower temperature (200 to 250°C), diethyl ether (DEE) was the major
product. It was found that Ru and Pt modification on HBZ catalyst can result in increased DEE yield at low reaction temperature due to increased
ethanol conversion without a significant change in DEE selectivity. By comparing the DEE yield of all catalysts in this study, the Ru-HBZ catalyst
apparently exhibited the highest DEE yield (ca. 47%) at 250°C. However, at temperature from 350 to 400°C, the effect of Ru and Pt was less
pronounced on ethylene yield. With various characterization techniques, the effects of Ru and Pt modification on HBZ catalyst were elucidated. It
revealed that Ru and Pt were present in the highly dispersed forms and well distributed in the catalyst granules. It appeared that the weak acid sites
measured by NH3 temperature-programmed desorption technique also decreased with Ru and Pt promotion. Thus, the increased DEE yields with the Ru and Pt
modification can be attributed to the presence of optimal weak acid sites leading to increased intrinsic activity of the catalysts. It can be
concluded that the modification of Ru and Pt on HBZ catalyst can improve the DEE yields by ca. 10%.
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Keras
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Lol, thanks for all the article you dig, but let's admit that most of them are not applicable to amateur chemistry. Certainly nice theoretical
resources, but of limited applicability at home.
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leau
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Catalytic dehydration of ethanol to ethylene and diethyl ether over alumina catalysts containing different phases with
boron modification
Ekrachan Chaichana, Nopparat Boonsinvarothai, Nithinart Chitpong & Bunjerd Jongsomjit
Journal of Porous Materials volume 26, pages 599–610 (2019)
The catalytic ethanol dehydration of ethanol over the solvothermal-derived alumina catalysts was investigated in this study. First, alumina catalysts
were synthesized by the solvothermal methods to obtain three different phase composition of alumina catalysts including γ-phase (G–Al), χ-phase
(C–Al) and equally mixed χ–γ phases (M–Al). Then, all catalysts were modified with boron (G–Al–B, C–Al–B and M–Al–B). It was found
that the boron modification increased the amounts of total acid sites and the ratio of weak to strong acid sites (WSR). The catalytic activity and
product selectivity of six catalysts via catalytic ethanol dehydration at 200, 300, and 400 °C were measured. For all catalysts, it revealed that
ethanol conversion increased with increased temperatures from 200 to 400 °C. At 200–300 °C, the unmodified catalysts tended to exhibit the higher
catalytic activity than the boron-modified catalysts. However, at high temperature (400 °C), the boron modification tended to increase the catalytic
activity, especially for the M–Al–B catalyst (complete ethanol conversion at 400 °C). Considering ethylene production, the M–Al–B exhibited
the highest ethylene yield among other catalysts with 92% at 400 °C. For diethyl ether, it was observed that the M–Al catalyst gave the highest
diethyl ether yield of 57% at 300 °C. This is because the boron modification increased the amounts of total acid sites, which can promote the
production of ethylene, while this is not preferable for diethyl ether production, which is favored by weak acid sites.
is attached
Attachment: chaichana2018.pdf (1.2MB) This file has been downloaded 178 times
[Edited on 19-9-2023 by leau]
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clearly_not_atara
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How convenient! Does it mention anything about the stability of the HBOB?
My guess is that its very high acidity would mean that you get a decent number of catalytic cycles per molecule HBOB before it decomposes by
esterification. That's presuming that the first step of decomposition is by transferring Et+ from EtOH2+ to BOB-. But experiment is king.
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leau
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Kinetic and mechanistic study of ethanol dehydration to diethyl ether over Ni-ZSM in a closed batch reactor a closed
batch reactor
Dayaram Tulsiram Sarve, Sunit Kumar Singh & Jayant D. Ekhe
Reaction Kinetics, Mechanisms and Catalysis volume 131, pages 261–281 (2020)
https://doi.org/10.1007/s11144-020-01847-z
In the present work, mechanistic pathways and kinetics of catalytic dehydration of ethanol were investigated in a closed batch reactor for the
formation of diethyl ether, and ethylene over the synthesized NiO loaded HZSM-5 in the range of 160–240 °C. The effect of the presence of water on
reaction performance was also evaluated. No significant negative impact of water over diethyl ether yield was observed up to 1:1 ethanol–water molar
ratio. The proposed two-step kinetic model highlights the mechanistically essential comparison between the strong (Brønsted) and weak (Lewis) acid
sites of catalyst for ethanol conversion to diethyl ether. Intramolecular dehydration of ethanol over strong acid sites led to ethylene formation.
Enhancement of weak acid sites due to NiO loading over HZSM-5 led to interestingly higher yields of diethyl ether by a combination of ethylene and
ethanol. Optimal consideration for maximum conversions was observed with high reusability.
is attached
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leau
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Influence of Phosphoric Acid Modification on Catalytic Properties of γ-χ Al2O3 Catalysts for Dehydration of Ethanol to
Diethyl Ether
Mutjalin Limlamthong, Nithinart Chitpong & Bunjerd Jongsomjit
Bulletin of Chemical Reaction Engineering & Catalysis 14 (1), 1-, 2019-04-15
DOI: 10.9767/bcrec.14.1.2436.1-8
In this present work, diethyl ether, which is currently served as promising alternative fuel for diesel engines, was produced via catalytic
dehydration of ethanol over H3PO4-modified g-c Al2O3 catalysts. The impact of H3PO4 addition on catalytic performance and characteristics of catalysts
was investigated. While catalytic dehydration of ethanol was performed in a fixed-bed microreactor at the temperature ranging from 200ºC to 400ºC
under atmospheric pressure, catalyst characterization was conducted by inductively coupled plasma (ICP), X-ray diffraction (XRD), N2 physisorption,
temperature-programmed desorption of ammonia (NH3-TPD) and thermogravimetric (TG) analysis. The results showed that although the H3PO4 addition tended
to decrease surface area of catalyst resulting in the reduction of ethanol conversion, the Al2O3 containing 5 wt% of phosphorus (5P/Al2O3) was the
most suitable catalyst for the catalytic dehydration of ethanol to diethyl ether since it exhibited the highest catalytic ability regarding diethyl
ether yield and the quantity of coke formation as well as it had similar long-term stability to conventional Al2O3 catalyst. The NH3-TPD profiles of
catalysts revealed that catalysts containing more weak acidity sites were preferred for dehydration of ethanol into diethyl ether and the adequate
promotion of H3PO4 would lower the amount of medium surface acidity with increasing catalyst weak surface acidity. Nevertheless, when the excessive
amount of H3PO4 was introduced, it caused the destruction of catalysts structure, which resulted in the catalyst incapability due to the decrease in
active surface area and pore enlargement.
is attached
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[Edited on 27-9-2023 by leau]
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leau
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Reaction of liquid sulphur trioxide with diethyl ether
Narula & Sharma
Indian Journal of Chemistry, Vol 16, pp 1106-8 (1978)
Addition of liquid sulfur trioxide to diethyl ether at low temperature results in the separation of a liquid adduct. Plots of the log of viscosity and
log of molar conductivity of the addition compound versus reciprocal of absolute temperature are linear. The activation energies of viscous flow and
ionic migration have been calculated from these plots.
is attached
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