摘要:
The invention relates to a process for preparing butadiene from n-butane comprising the steps (A) providing an n-butane-containing feed gas stream, (B) feeding the n-butane-containing feed gas stream into a first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to 1-butene, 2-butene and optionally butadiene to obtain a first product gas stream comprising n-butane, 1-butene and 2-butene, with or without butadiene and secondary components, (C) feeding the first product gas stream comprising n-butane, 1-butene and 2-butene, with or without butadiene and secondary components, into a second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to butadiene to give a second product gas stream comprising butadiene, n-butane and steam, with or without secondary components, (D) recovering butadiene from the second product gas stream.
摘要:
Catalysts for preparing carboxylic acid salts from alcohols which a) consist of copper or b) comprise from 99.9 to 10% by weight of copper and from 0.01 to 90% by weight of iron and from 0 to 50% by weight of one or more other metals, and may optionally be doped, the hydroxides being obtained by precipitation of copper salt solutions or by coprecipitation of copper and iron salt solutions optionally containing salts of other metals using a base, and being reduced by hydrogen.
摘要:
In a process for the catalytic gas-phase oxidation of propene to acrolein, the reaction gas starting mixture is passed with a propene loading of ≧160 l(S.T.P.)/l·h over a fixed-bed catalyst which is housed in two spatially successive reaction zones A,B, the reaction zone B being kept at a higher temperature than the reaction zone A.
摘要:
Carbonyl compounds of the formula where R1 is a hydrogen atom or an alkyl radical having from 1 to 3 carbon atoms, R2 is a hydrogen atom, an unsubstituted or C1-C3-alkyl-monosubstituted to -trisubstituted C2-C4-alkenyl radical or a radical of the formula where R3 is a hydrogen atom or together with R4 is an oxygen atom, R4 is the radical OR6 or together with R3 is an oxygen atom, R5 is a hydrogen atom, an alkyl radical having from 1 to 8 carbon atoms, an unsubstituted or C1-C3-alkyl-monosubstituted to -trisubstituted C2-C4-alkenyl radical or a cyclohexyl or cyclopentyl radical and R6 is an alkyl radical having from 1 to 4 carbon atoms, a cyclohexyl or cyclopentyl radical or a radical of the formula —CH2—CHO or —CH2—CH2—O—CH2—CHO, are prepared by gas-phase oxidation of methanol or alcohols of the formula where R1 and R5 are as defined above, by means of an oxygen-containing gas in the presence of copper- and/or silver-containing catalysts, the catalyst system used comprising at least one phosphorus-containing copper- and/or silver-containing catalyst.
摘要:
The invention relates to a method of controlling a hydrogenation of a starting material in a hydrogenation reactor, in which the amount of hydrogen reacted in the hydrogenation is firstly determined, the ratio of the amount of hydrogen reacted to the amount of starting material fed in is then derived, this ratio is compared with a prescribed value and, finally, at least one process parameter is altered if the ratio of the amount of hydrogen reacted to the amount of starting material fed in deviates by a prescribed amount from the prescribed value.
摘要:
The present invention relates to the technical field of storing gas including methane and hydrogen, in particular to the fuel cell technology. In particulars it relates to a method of using a metallo-organic framework material comprising pores and at least one metal ion and at least one at least bidentate organic compound.
摘要:
A methanol reforming catalyst containing passivated copper and zinc oxide and/or alumina can be prepared by (1) precipitating or spray-drying a mixture of catalyst precursor components dissolved or suspended in a diluent in order to form a solid catalyst precursor in the form of powder or granules, (2) calcining and reducing the solid catalyst precursor obtained in stage (1), (3) passivating the reduced catalyst precursor obtained in stage (2) and (4) shaping the passivated catalyst precursor obtained in stage (3) to form the catalyst. A reduction in the volume shrinkage and an increase in the mechanical hardness during operation of the methanol reforming catalyst are achieved by the preparation process.
摘要:
A catalyst suitable for the gas-phase oxidation of organic compounds to α,β-unsaturated aldehydes and/or carboxylic acids and having an active phase comprising a multimetal oxide material is prepared by a process in which a particulate catalyst precursor which contains oxides and/or compounds of the elements other than oxygen which constitute the multimetal oxide material, which compounds can be converted into oxides, is prepared and said catalyst precursor is converted by calcination into a catalytically active form, wherein a stream of the particulate catalyst precursor is passed at substantially constant speed through at least one calcination zone at constant temperature for calcination.
摘要:
A layered catalyst support or carrier provides a core member for carrying out non-steady state heterogeneously catalyzed processes where reaction gases and their products come in contact with a conventional catalyst applied to the carrier. The support as a carrier is made up of a large number of individually shaped particulate bodies or monolithic packings to be loaded into a reactor and maintained as a fluidized bed or a fixed bed during the non-steady state reaction and the recovery of the products. The support or carrier may consist of glass, quartz, oxides, nitrides, aluminosilicates, magnesium silicates, metals and carbon or their mixtures. Each shaped particle or monolithic packing of this core support is then completely enclosed by depositing thereon a thin protective layer of a nitride, oxide, carbide or chloride of a metal, a non-metal or a mixture thereof, which exhibits a dense, pore-free microstructure and a nonpolar surface having a very low density of acid centers. This outer layer is applied to the core support by a plasma-assisted gas phase deposition. The catalytically active layer is then applied to this protective layer.
摘要:
A novel delayed-release form for pharmaceutical active compounds, characterized by a core containing the active compound and a diffusion-inhibiting, adhesive coating layer having a thickness in the range from 0.01 to 10 .mu.m, consisting of a chemical network which has been applied to the support in a plasma-assisted chemical deposition process, and a process for its production are described.