Abstract: The invention relates to a process for preparing a silver catalyst suitable for use in the oxidation of ethylene to ethylene oxide characterized in that an alkali metal enriched alumina carrier, which has been calcined, is impregnated with a solution of a silver compound, sufficient to cause precipitation on the carrier of from 1 to 25 percent by weight, on the total catalyst, of silver, and before, during or after that impregnation also with one or more dissolved potassium, rubidium or cesium compounds as promoter and with a rhenium compound, and after precipitation the silver compound on the impregnated carrier is reduced to metallic silver.

Abstract: Ethylene oxide is produced by contacting ethylene and oxygen in the presence of a chlorine containing reaction modifier with a silver containing catalyst, nitropropane being also present. The nitropropane raises the selectivity of the process.

Abstract: This invention relates to an ethylene oxide catalyst having an improved selectivity which catalyst comprises silver, a promoting amount of alkali metal, a promoting amount of rhenium and a promoting amount of rhenium co-promoter selected from sulfur, molbydenum, tungsten, chromium and mixtures thereof supported on a porous refractory support.

Abstract: This invention relates to an ethylene oxide catalyst having an improved selectivity which catalyst comprises silver, a promoting amount of alkali metal, a promoting amount of rhenium and a promoting amount of rhenium co-promoter selected from sulfur, molbydenum, tungsten, chromium and mixtures thereof supported on a porous refractory support.

Abstract: A supported silver catalyst having improved thermostability is prepared by depositing silver particles on a carrier or support having a stepped structure.

Abstract: The invention relates to a process for the preparation of a silver-containing catalyst suitable for the oxidation of ethylene to ethylene oxide which comprises(a) mixing alumina with a tin compound and with an alkali metal compound,(b) calcining the mixture to obtain an alkali-enriched and tin containing alumina carrier,(c) applying a silver compound to the alumina carrier and converting said silver compound to metallic silver.The catalyst has a high activity, a high selectivity combined with a very high stability.

Abstract: This invention relates to an ethylene oxide catalyst having an improved selectivity which catalyst comprises silver, a promoting amount of alkali metal, a promoting amount of rhenium and a promoting amount of rhenium co-promotor selected from sulfur, molbydenum, tungsten, chromium and mixtures thereof supported on a porous refractory support.

Abstract: This invention relates to an ethylene oxide catalyst having an improved selectivity which catalyst comprises silver, a promoting amount of alkali metal and a promoting amount of rhenium supported on a porous refractory support.

Abstract: This invention relates to ethylene oxide catalysts comprising silver, alkali metal promoters supported on a carrier, which carrier is prepared by a process which comprises mixing an aluminum compound with an alkali metal salt and with a silicon compound and calcining resultant mixture at a temperature greater than about 1100.degree. C.

Abstract: This invention relates to ethylene oxide catalysts comprising silver, alkali metal promoters supported on a carrier, which carrier is prepared by a process which comprises mixing an aluminum compound with a tin compound and calcining resultant mixture at a temperature greater than about 1100.degree. C.

Abstract: The Al.sub.2 O.sub.3 carrier material from Ag/Al.sub.2 O.sub.3 supported catalysts which is obtained after the silver has been removed from such spent catalysts in a conventional manner is regenerated by a method in which the carrier material(a) is treated with an aqueous solution of a water-soluble salt or hydroxide of a metal of group IIA, IIIB or IVB of the Periodic Table or of aluminum, copper, manganese, zinc, cadmium, tin or lead, and the material treated in this manner is then dried, and/or the material(b) is heated at 750-1,500.degree. C. for not less than 10 minutes.

Abstract: The invention relates to novel benzodioxole derivatives of the formula I ##STR1## in which R.sub.1 represents an unsubstituted or substituted, aromatic or heteroaromatic radical, alk represents an alkylene or alkylidene radical having a maximum of 5 carbon atoms, n represents O or 1, R.sub.2 and R.sub.3 each represents, independently of the other, hydrogen, lower alkyl, lower alkoxy or halogen, and A represents the radical O-R.sub.4, wherein R.sub.4 represents hydrogen or an unsubstituted or substituted, aliphatic or araliphatic hydrocarbon radical, or A represents the radical ##STR2## in which either R.sub.5 and R.sub.6 each represents, independently of the other, hydrogen or lower alkyl, or R.sub.5 and R.sub.6 are bonded to one another and, together with the adjacent nitrogen atom, represent unsubstituted or lower alkyl-substituted tetra- or hexa-methyleneimino or 4-morpholinyl, to salts of compounds of the formula I in which A represents OR.sub.4 wherein R.sub.

Abstract: The performance of a silver on alumina catalyst for the oxidation of ethylene to ethylene oxide is improved by the inclusion, in the raw mix for the carrier of an oxide, or oxide precursor, of zinc, lanthanum, or magnesium in the amount of 7 to 40%, calculated as the oxide.

Abstract: Process for activating or reactivating silver substrate catalysts having promoter metals used in the production of ethylene oxide by oxidizing ethylene with oxygen or with gases containing oxygen.At least part of the mixture of reaction gases is made to pass at least in part through a bed arranged before the catalyst zone, this bed containing uniformly distributed compounds of the promoter metals.

Abstract: A method of preparing a supported catalyst of a gold-silver alloy useful for making ethylene oxide by applying a gold salt to a suitable support, reducing it to gold metal, then applying a silver salt and reducing it to silver, thereby forming a gold-silver alloy by diffusion, on the support.