摘要:
A process for the catalytic gas-phase oxidation of propene to acrylic acid, in which the reaction gas starting mixture is oxidized, with an increased propene loading, in a first reaction stage, over a first fixed-bed catalyst and then the acrolein-containing product gas mixture of the first reaction stage is oxidized, in a second reaction stage, with an increased acrolein loading, over a second fixed-bed catalyst, the catalyst moldings in both reaction stages having an annular geometry.
摘要:
In a process for the catalytic gas-phase oxidation of acrolein to acrylic acid, the reaction gas starting mixture is passed, with an acrolein loading of ≧150 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:
Cesium based multimetal oxide compositions which are suitable as catalysts for the gas-phase-catalytic oxidative preparation of methacrolein from isobutene or tert-butanol or its methyl ether. The catalysts are characterized by increased selectivity for the formation of methacrolein. The catalysts have locally delimited regions of an oxide composition, preferably (Bi.sub.2 W.sub.2 O.sub.9), surrounded by the remaining constituents of the multimetal oxide.
摘要翻译:铯基多金属氧化物组合物,其适合作为用于从异丁烯或叔丁醇或其甲基醚气相催化氧化制备甲基丙烯醛的催化剂。 催化剂的特征在于增加甲基丙烯醛形成的选择性。 催化剂具有由多金属氧化物的剩余组分包围的氧化物组合物优选(Bi 2 W 2 O 9)的局部限定区域。
摘要:
The invention relates to a method for producing acrylic acid by the heterogeneously catalysed gas-phase oxidation of propane on a multi-metal oxide mass, said mass containing the elements Mo, V, Te and/or Sb and having a specific X-ray diffractogram.
摘要:
In a process for the preparation of acrolein and/or acrylic acid from propane, the propane is subjected, in a first reaction stage, to a partial oxydehydrogenation with molecular oxygen under homogeneous and/or heterogeneous catalysis to give propene and the product gas mixture formed in the first reaction stage is then used for the preparation of acrolein and/or acrylic acid by gas-phase catalytic propene oxidation.
摘要:
Multimetal oxides containing Mo, V and at least one of the elements W, Nb, Ti, Zr, Hf, Ta, Cr, Si and Ge and having a special three-dimensional atomic arrangement are used in catalysts for the catalytic gas-phase oxidation of organic compounds.
摘要:
In a process for the preparation of catalytically active poly-metal oxide materials containing Mo and V, a catalyst intermediate is calcined at from 300.degree. to 450.degree. C. in a gas atmosphere which, in addition to inert gases and/or steam, consists of from 0.5 to 4% by volume of O.sub.2 and, averaged over the calcination time, from 1 to 8% by volume of NH.sub.3.
摘要:
Multimetal oxide compositions having a two-phase structure and comprising molybdenum, hydrogen, one or more of the elements phosphorus, arsenic, boron, germanium and silicon, one or more of the elements niobium, tantalum and antimony and one or more of the elements copper, iron, cobalt, nickel, zinc, cadmium, manganese, magnesium, calcium, strontium and barium, and their use for the preparation of methacrylic acid by gas-phase catalytic oxidation.
摘要:
Multimetal oxide compositions which comprise, as basic constituents, the elements Mo, V, W, Cu and Ni in oxidic form in certain molar ratios, and the preparation of these multimetal oxide compositions, and their use as catalysts for the gas-phase catalytical oxidation of acrolein to acrylic acid.
摘要:
Multimetal oxide compositions which comprise, as basic constituents, the elements Mo, V, W, Cu and Ni in oxidic form in certain molar ratios, and the preparation of these multimetal oxide compositions, and their use as catalysts for the gas-phase catalytical oxidation of acrolein to acrylic acid.