Abstract: Fouling of the acetic acid saturator by recycle gas in the continuous gas phase process for manufacture of vinyl acetate is reduced by adding an N-oxyl fouling inhibitor to the saturator and/or at one or more other addition sites in the process, in amounts such that the concentration of N-oxyl compound which accumulates in the saturator bottoms is from 10 to 100 ppm. The amount of N-oxyl compound in the saturator is preferably from 10-50 ppm. The reduction in fouling is evidenced by lessening the lowering of the heat transfer coefficient of the saturator over time.

Abstract: Addition of an N-oxyl compound to points in the VAM synthesis process such that from 10 to 100 ppm of N-oxyl compound is present in the column bottoms of the acetic acid separator markedly reduce fouling in the separator, thus allowing long and efficient VAM production campaigns.

Abstract: The invention relates to a method for removing oxygen from hydrocarbon-containing gas mixtures, characterized in that a hydrocarbon-containing gas mixture containing 50 vol % of one or more hydrocarbons, 2 to 10 vol % of oxygen, and possibly one or more gases from the group comprising nitrogen, noble gases, hydrogen, carbon dioxide, carbon monoxide, and water is introduced into an isothermally operated reactor, in which the oxygen contained in the hydrocarbon-containing gas mixture is at least partially converted into carbon dioxide and water in the presence of one or more catalysts, wherein the specifications in vol % relate to the total volume of the hydrocarbon-containing gas mixture introduced into the reactor and add up to 100 vol % in total.

Abstract: Oxygen is effectively removed from hydrocarbon-containing gas streams while minimizing danger of explosion by contacting the gas stream with a catalyst comprising shaped bentonite supports having an outer shell containing catalytic metals gold, and at least one of palladium platinum, rhodium, or iridium.

Abstract: Oxygen is effectively removed from hydrocarbon-containing gas streams while minimizing danger of explosion by contacting the gas stream with a catalyst comprising shaped bentonite supports having an outer shell containing catalytic metals gold, and at least one of palladium platinum, rhodium, or iridium.

Abstract: The invention relates to a method for removing oxygen from hydrocarbon-containing gas mixtures, characterized in that a hydrocarbon-containing gas mixture containing 50 vol % of one or more hydrocarbons, 2 to 10 vol % of oxygen, and possibly one or more gases from the group comprising nitrogen, noble gases, hydrogen, carbon dioxide, carbon monoxide, and water is introduced into an isothermally operated reactor, in which the oxygen contained in the hydrocarbon-containing gas mixture is at least partially converted into carbon dioxide and water in the presence of one or more catalysts, wherein the specifications in vol % relate to the total volume of the hydrocarbon-containing gas mixture introduced into the reactor and add up to 100 vol % in total.

Abstract: The invention provides a process for preparing vinyl acetate in a heterogeneously catalyzed, continuous gas phase process by reacting ethylene with acetic acid and oxygen and subsequently working up the product gas stream, with inhibition of the polymerization of vinyl acetate during the workup of the product gas mixture by addition of one or more N-oxyl compounds which contain at least one N-oxyl radical group —N—O. as inhibitors which comprises adding the N-oxyl compound as a 50 to 85% by weight strength aqueous solution.

Abstract: The invention provides a process for preparing vinyl acetate in a heterogeneously catalyzed, continuous gas phase process by reacting ethylene with acetic acid and oxygen and subsequently working up the product gas stream, with inhibition of the polymerization of vinyl acetate during the workup of the product gas mixture by addition of one or more N-oxyl compounds which contain at least one N-oxyl radical group —N—O. as inhibitors which comprises adding the N-oxyl compound as a 50 to 85% by weight strength aqueous solution.

Abstract: The invention provides a process for preparing vinyl acetate monomer (VAM) by reacting ethylene with acetic acid and oxygen in a tube bundle reactor in a heterogeneously catalysed, continuous gas phase process, characterized in that a high-performance catalyst with a space-time yield of more than 700 g of VAM/l of catalyst×hour is used for catalysis, and in that the tube bundle reactor comprises tubes with a ratio of inner surface area to volume of ?130 m?1.

Abstract: The invention relates to a method for producing vinyl acetate in a heterogeneously catalyzed, continuous gas-phase process by reacting ethylene with acetic acid and oxygen in a reactor, and a) separating the product gas flow essentially containing ethylene, vinyl acetate, acetic acid, water, carbon dioxide, and other inert gases, and b) feeding a circulating gas flow containing ethylene and CO2 back into the reactor, c) the circulating gas flow being compressed in a circulating gas compressor before being fed back into the reactor, and d) a partial flow of the circulating gas is branched off on the suction side or the pressure side of the circulating gas compressor and is fed to a CO2 scrubbing process, and e) is scrubbed in a water scrubber before the CO2 scrubbing process, characterized in that f) after the CO2 scrubbing process, the partial flow, together with ethylene as a propellant, is fed, by means of a jet compressor, to the circulating gas on the pressure side of the circulating gas compressor and do

Abstract: A method for producing vinyl acetate in a heterogeneously catalyzed, continuous gas phase process by reacting ethylene with acetic acid and oxygen in a reactor and separating the product gas stream substantially comprising ethylene, vinyl acetate, acetic acid, water, carbon dioxide and inert gases.

Abstract: A method for producing vinyl acetate in a heterogeneously catalyzed, continuous gas phase process by reacting ethylene with acetic acid and oxygen in a reactor and separating the product gas stream substantially comprising ethylene, vinyl acetate, acetic acid, water, carbon dioxide and inert gases.

Abstract: A process for preparing unsaturated carboxylic esters includes reaction of alkenes having 2 to 6 carbon atoms with alkanecarboxylic acids having 1 to 6 carbon atoms in the presence of an oxygenous gas and in the presence of a heterogeneous noble metal catalyst by means of a continuous homogeneous gas phase process in a reactor. A gaseous phase (cycle gas) is circulated, and the cycle gas is laden with alkanecarboxylic acid in an acid saturator before entry into the reactor. In a presaturator connected upstream of the acid saturator, the cycle gas is laden with a portion of the amount of alkanecarboxylic acid used for saturation, and then it is transferred to the acid saturator and laden there with the remaining amount of alkanecarboxylic acid.

Abstract: The invention relates to a method for producing vinyl acetate in a heterogeneously catalyzed, continuous gas-phase process by reacting ethylene with acetic acid and oxygen in a reactor, and a) separating the product gas flow essentially containing ethylene, vinyl acetate, acetic acid, water, carbon dioxide, and other inert gases, and b) feeding a circulating gas flow containing ethylene and CO2 back into the reactor, c) the circulating gas flow being compressed in a circulating gas compressor before being fed back into the reactor, and d) a partial flow of the circulating gas is branched off on the suction side or the pressure side of the circulating gas compressor and is fed to a CO2 scrubbing process, and e) is scrubbed in a water scrubber before the CO2 scrubbing process, characterized in that f) after the CO2 scrubbing process, the partial flow, together with ethylene as a propellant, is fed, by means of a jet compressor, to the circulating gas on the pressure side of the circulating gas compressor and do

Abstract: The invention provides a process for preparing vinyl acetate monomer (VAM) by reacting ethylene with acetic acid and oxygen in a tube bundle reactor in a heterogeneously catalysed, continuous gas phase process, characterized in that a high-performance catalyst with a space-time yield of more than 700 g of VAM/l of catalyst×hour is used for catalysis, and in that the tube bundle reactor comprises tubes with a ratio of inner surface area to volume of ?130 m-1.

Abstract: The invention provides a process for preparing unsaturated carboxylic esters by means of reaction of alkenes having 2 to 6 carbon atoms with alkanecarboxylic acids having 1 to 6 carbon atoms in the presence of an oxygenous gas and in the presence of a heterogeneous noble metal catalyst by means of a continuous homogeneous gas phase process in a reactor, wherein a gaseous phase (cycle gas) is circulated, and the cycle gas is laden with alkanecarboxylic acid in an acid saturator before entry into the reactor, characterized in that, in a presaturator connected upstream of the acid saturator, the cycle gas is laden with a portion of the amount of alkanecarboxylic acid used for saturation, then it is transferred to the acid saturator and laden there with the remaining amount of alkanecarboxylic acid.

Abstract: The efficiency of vinyl acetate production is increased by scrubbing of off gas followed by CO2 absorption. A portion of the off gas containing substantial quantities of ethylene is recycled to the process, whereas another portion is employed in another ethylene consuming reaction. Despite not removing non-reactive gases, selectivity and yield based on ethylene are both increased.

Abstract: The efficiency of vinyl acetate production is increased by scrubbing of off gas followed by CO2 absorption. A portion of the off gas containing substantial quantities of ethylene is recycled to the process, whereas another portion is employed in another ethylene consuming reaction. Despite not removing non-reactive gases, selectivity and yield based on ethylene are both increased.

Abstract: A carrier catalyst containing copper and alkali ions on an annular carrier of surface-active material is defined by the dimensions of the carrier body and the porosity of the finished catalyst. Its total pore volume is 0.6-1.0 ml/g, pores smaller than 4 nm diameter are not present, pores of 8-20 nm diameter constitute at least 80% of the total pore volume and the remainder consists of macropores with a diameter greater than 20 nm (i.e., up to 200 nanometers). The catalyst is suitable for the production of 1,2-dichloroethane by means of the oxychlorination of ethylene.

Abstract: In the process, a copper/rhodium catalyst impregnated with 0.1 to 10.0% by weight, based on the total weight of active charcoal catalyst support and active components, of a water-soluble phosphonium halide is employed for the preparation of trichloroelethylene from perchloroethylene and hydrogen.