75-21-8Relevant articles and documents
Alkali Metal, Chlorine and other Promoters in the Silver-catalysed Selective Oxidation of Ethylene
Grant, Robert B.,Harbach, Christopher A. J.,Lambert, Richard M.,Tan, S. Aun
, p. 2035 - 2046 (1987)
Ethylene oxidation over well characterised Ag(111) surfaces has been investigated by temperature-programmed reaction measurements and by differential batch reactor studies at pressures up to 50 Torr.The influence of chlorine predosing on catalytic activity indicates that a chemisorbed atomic oxygen species is responsible for both partial oxidation and complete oxidation to CO2 + H2O.This tends to be confirmed by experiments using N2O as the oxidant, both with the single crystal specimen and with a practical Ag-αAl2O3 catalyst in a flow microreactor.Dissolved oxygen, like adsorbed chlorine, is found to be a selectivity promoter.Adsorbed Cs also increases the rate of ethylene oxide production but can also positively influence the overall activity of the system.The results suggest that chlorine and dissloved oxygen promoters principally affect the primary chemistry, whereas the main effect of Cs is on the secondary chemistry (further oxidation of ethylene oxide).This view tends to be confirmed by temperature-programmed reaction measurements and by direct experiments on the influence of Cl and Cs on the isomerisation and combustion of ethylene oxide itself.It is suggested that these effects are primarily electronic in origin and a mechanism based on this view is presented.In the presence of Cs, both CO2 and NOx can act as selectivity promoters for the formation of ethylene oxide.
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Reyerson,Oppenheimer
, p. 290 (1944)
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Epoxidation of Ethylene over Silver Catalysts modified by Sodium Chloride
Ayame, Akimi,Takeno, Noboru,Kanoh, Hisao
, p. 617 - 618 (1982)
The selectivity of epoxide synthesis in the direct oxidation of ethylene is increased to 85-87percent by addition of sodium chloride to the silver catalyst; this selectivity corresponds to the maximum expected by mechanistic studies.
XPS study of the size effect in ethene epoxidation on supported silver catalysts
Bukhtiyarov, Valery I.,Prosvirin, Igor P.,Kvon, Ren I.,Goncharova, Svetlana N.,Bal'zhinimaev, Bair S.
, p. 2323 - 2329 (1997)
Supported silver catalysts (Ag/α-Al2O3) with different particle sizes (100-1000 A?) have been prepared and studied by XPS. It has been shown that the increase in the ethene epoxidation rate with silver particle size (size effect) is
Cs-Promoted Ag(111): Model Studies of Selective Ethylene Oxidation Catalysts
Campbell, Charles T.
, p. 5789 - 5795 (1985)
The role of cesium promoters in silver catalysts for the selective epoxidation of ethylene (C2H4 + 1/2O2 -> C2H4O) has been studied by using adsorbed cesium on the surface of clean Ag(111) as a model catalysts.The experiments are performed in an apparatus
Orzechowski,MacCormack
, p. 388,393,432,443 (1954)
Thio Diels-Alder reactions of α,β-unsaturated 1,3-oxathiolanes with aliphatic olefins and 1,3-dienes
Kerverdo, Sébastien,Lizzani-Cuvelier, Louisette,Du?ach, Elisabet
, p. 8841 - 8844 (2003)
A series of α,β-unsaturated 1,3-oxathiolanes reacted with aliphatic olefins such as norbornene and with various 1,3-dienes in the presence of TiCl4 leading to dihydrothiapyrans, via a cycloaddition-type reaction. The unsaturated oxathiolanes acted as masked heterodienes in this thio Diels-Alder reaction.
Wan
, p. 234 (1953)
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Force,Bell
, p. 175,176-178 (1976)
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PROCESS FOR PRODUCING ETHYLENE OXIDE FROM ETHANE BY OXIDATIVE DEHYDROGENATION AND EPOXIDATION WITH SPLIT RECYCLE
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Paragraph 0079; 0083, (2021/09/17)
An ethylene oxide (EO) production process comprising (a) introducing a first reactant mixture (C2H6, O2) to a first reactor to produce a first effluent stream (C2H4,C2H6,O2); (b) introducing a second reactant mixture to a second reactor to produce a second effluent stream (EO, C2H4,C2H6,O2); wherein the second reactant mixture comprises at least a portion of first effluent stream; (c) separating the second effluent stream into an EO product stream (EO) and recycle stream (C2H4,C2H6,O2); wherein ethylene is not separated from recycle stream and/or first effluent stream; and (d) recycling a first portion of recycle stream to the first reactor, and a second portion of recycle stream to the second reactor; wherein recycle split ratio 0.6; and wherein recycle split ratio is defined as ratio of volumetric flowrate of first portion of recycle stream divided by the sum of volumetric flowrates of first portion and second portion of recycle stream.
Chemical Behaviour of CaAg2 under Ethylene Epoxidation Conditions
Antonyshyn, Iryna,Sichevych, Olga,Rasim, Karsten,Ormeci, Alim,Burkhardt, Ulrich,Titlbach, Sven,Schunk, Stephan Andreas,Armbrüster, Marc,Grin, Yuri
, p. 3933 - 3941 (2018/09/10)
The binary compound CaAg2 is examined as a catalyst for the ethylene epoxidation reaction. During the induction phase, conversion and selectivity increase and then remain stable for several hundred hours. The presence of ethyl chloride as a promoter is crucial. The pristine CaAg2 reacts with the gaseous reactants and forms a porous microstructure of calcium-containing oxidation products on the surface, in which particles of elemental silver are embedded. The microstructure is remarkably stable, and in particular, prevents further sintering of the silver particles.
