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.
In situ controlled promotion of catalyst surfaces via solid electrolytes: the NEMCA effect
Vayenas,Yentekakis,Bebelis,Neophytides
, p. 1393 - 1401 (1995)
The catalytic activity and selectivity of metal films interfaced with solid electrolytes can be varied in situ in a dramatic and reversible manner by applying currents or voltages (typically ± 1-2 V) between the catalyst film and a counter electrode also
A Nanoarchitecture Based on Silver and Copper Oxide with an Exceptional Response in the Chlorine-Promoted Epoxidation of Ethylene
Ramirez, Adrian,Hueso, Jose L.,Suarez, Hugo,Mallada, Reyes,Ibarra, Alfonso,Irusta, Silvia,Santamaria, Jesus
, p. 11158 - 11161 (2016)
The selective oxidation of ethylene to ethylene epoxide is highly challenging as a result of competing reaction pathways leading to the deep oxidation of both ethylene and ethylene oxide. Herein we present a novel catalyst based on silver and copper oxide
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.
Study of the Real Structure of Silver Supported Catalysts of Different Dispersity
Tsybulya, S. V.,Kryukova, G. N.,Goncharova, S. N.,Shmakov, A. N.,Bal'zhinimaev, B. S.
, p. 194 - 200 (1995)
The real structure of silver supported catalysts for ethylene epoxidation (Ag/α-Al2O3) was investigated using precision X-ray diffraction on synchrotron radiation, in situ high-temperature X-ray diffraction, and transmission electron microscopy.Stacking f
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
Direct conversion of ethane to ethylene oxide over Ni-Ag-O catalyst
Wu, Ying,Wu, Binfu,He, Yiming,Wu, Tinghua
, p. 284 - 285 (2009)
Ethylene oxide was directly synthesized by oxidation of ethane over Ni-Ag-O catalyst with ethane conversion of 10% and ethylene oxide yield of 1.2% at 310°C. NiOx and Ag in the catalyst favor ethane activation and the formation of ethylene oxid
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
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.
PRODUCTION PROCESS OF ALKYLENE OXIDES FROM ALKYLENE CARBONATES
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Page/Page column 10-12, (2022/04/03)
Catalytic process for producing alkylene epoxide, selected between ethylene oxide or propylene oxide, from the corresponding alkylene carbonate, selected between ethylene carbonate or propylene carbonate, comprising the decomposition reaction of alkylene carbonate, in the presence of sodium bromide as catalyst, in which: the reaction temperature is between 207 and 245°C, and the catalyst is in amounts comprised between 5x10-4 and 8x10-3 moles per mole of alkylene carbonate. This process can be carried out continuously. A further object of the invention is the modular plant which allows carrying out such a process.
