Abstract: The subject invention relates to a process for regenerating silver-containing carrier catalysts used in the preparation of ethylene oxide which comprises treating a deactivated catalyst with a solution comprising a potassium, rubidium, or cesium compound and a reducing agent. The subject process provides improved catalyst regeneration.

Abstract: C.sub.2 -C.sub.4 -olefins are prepared by catalytic conversion of methanol and/or dimethyl ether in the presence of a zeolite catalyst at elevated temperatures, by a process in which the catalyst used is a pure borosilicate zeolite which has been tableted or extruded without a binder and treated with hydrofluoric acid and hydrochloric acid. The treatment of the catalyst with hydrofluoric acid is carried out using 0.001-1N HF, and that with hydrochloric acid is carried out using 3-25% strength acid. The time-on-stream of the catalyst is improved.

Abstract: C.sub.2 -C.sub.4 -olefins are prepared by catalytic conversion of methanol and/or dimethyl ether in the presence of a zeolite catalyst at elevated temperatures by a process wherein the catalyst used is a borosilicate zeolite which is treated with hydrogen fluoride, molded together with an amorphous aluminosilicate as a binder and then treated with hydrochloric acid.

Abstract: A process for the preparation of a crystalline aluminosilicate of the pentasil type by hydrothermal crystallization of SiO.sub.2 and Al(OH).sub.3 in the presence of an alkali metal salt at from 80.degree. to 250.degree. C., wherein the crystallization is carried out in ether or aqueous ether. Particularly suitable solvents include the ethers from the group of the poly-(ethylene glycol) dimethyl ethers and mixtures of these ethers with water. The use of these crystalline aluminosilicates as catalysts for alkylating aromatics, and for preparing olefins and/or aromatics from methanol and/or dimethyl ether is also described.

Abstract: A process for the preparation of olefins from methanol and/or dimethyl ether by conversion in the presence of a zeolite catalyst, in particular a borosilicate zeolite, at elevated temperature, with the addition of a small amount of an electron donor.

Abstract: A process for the preparation of lower olefins from methanol or dimethyl ether by catalytic conversion at from 300.degree. to 550.degree. C. in two stages over borosilicate zeolites, wherein C.sub.2 -C.sub.4 -olefins and C.sub.1 -C.sub.4 -paraffins are removed after the first reaction stage, the C.sub.5.sup.+ hydrocarbons are passed to the second reaction stage, the aromatics are removed from the reaction product of the second stage and the remaining reaction products are recycled. The advantage of this process is an improvement in the yield of olefins.

Abstract: The process for the preparation of olefins by converting methanol and/or dimethyl ether in the presence of a zeolite catalyst is improved by treating the catalyst with hydrogen fluoride. Aluminosilicate zeolites and borosilicate zeolites, especially those of the pentasil type, are chiefly used.

Abstract: Supported catalysts containing silver and alkali metals, for the preparation of ethylene oxide from ethylene and oxygen in the gas phase, are prepared or regenerated by modifying, respectively, a new or spent supported catalyst which already contains metallic silver and may or may not contain the light alkali metals lithium and/or sodium and, where a spent catalyst is concerned, also contains the heavy alkali metals potassium, rubidium and/or cesium, with a solution containing the heavy alkali metals, the modifier solution used containing(a) a surfactant and/or a reducing agent, in the case of the preparation of a new catalyst or(b) a surfactant, in the case of the regeneration of a spent catalyst.

Abstract: A catalyst for the manufacture of ethylene oxide, giving improved yield and having a long life, based on an alkali metal-modified silver catalyst on an oxide carrier is obtained by providing the silver-containing catalyst, in the reduced state, with the alkali metal by applying an alcoholic alkali metal salt solution which also contains an organic oxygen compound or nitrogen compound which forms complexes with silver ions.

Abstract: A novel catalyst for the manufacture of ethylene oxide from ethylene by means of oxygen or air, comprising from 2 to 12% of silver on a conventional carrier, together with from 0.1 to 2 atom% (based on silver) of lithium and from 0.05 to 0.35 atom% of potassium or 0.003 to 0.25 atom% of rubidium or 0.0005 to 0.2 atom% of cesium or mixtures of potassium, rubidium and/or cesium in amounts exhibiting corresponding catalytic activity. The catalyst is advantageously obtained by heating a carrier which is impregnated with a silver complex compound.