摘要:
An active and selective hydrocarbon partial oxidation catalyst comprises an activated partially-reduced polyoxometallate, preferably niobium polyoxomolybdate, that is prepared from a suitable polyoxoanion, which has been exchanged with a suitable cation and activated by heating to an activation effective temperature in the presence of a suitable reducing agent such as pyridinium. C3 and C4 hydrocarbons may be partially oxidized selectively to acrylic acid and maleic acid.
摘要翻译:活性和选择性烃部分氧化催化剂包含活化的部分还原的多金属氧酸盐,优选铌聚氧钼酸盐,其由合适的多氧阴离子制备,其已经与合适的阳离子交换并通过在存在下加热至活化有效温度而被活化 合适的还原剂如吡啶鎓。 C 3和C 4烃可以部分地被氧化成丙烯酸和马来酸。
摘要:
Improved processes for the preparation of olefins, unsaturated carboxylic acids and unsaturated nitriles involve the use of dehydrogenation catalysts suitable for the conversion of alkanes to alkenes and catalysts suitable for the conversion of alkanes and/or alkenes to unsaturated carboxylic acids or unsaturated nitriles.
摘要:
Alkenes, unsaturated saturated carboxylic acids, saturated carboxylic acids and their higher analogues are prepared directly from corresponding alkanes utilizing using a mixed bed catalyst at flame temperatures in a short contact time reactor.
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:
A mixed metal oxide, which may be an orthorhombic phase material, is improved as a catalyst for the production of unsaturated carboxylic acids, or unsaturated nitriles, from alkanes, or mixtures of alkanes and alkenes, by: contacting with a liquid contacting member selected from the group consisting of organic acids, alcohols, inorganic acids and hydrogen peroxide to form a contact mixture; recovering insoluble material from the contact mixture; and calcining the recovered insoluble material in a non-oxidizing atmosphere.
摘要:
A mixed metal oxide Mo--V--Ga--Pd--Nb--X (where X=La, Te, Ge, Zn, Si, In or W) catalytic system providing a higher selectivity to acrylic acid in the low temperature partial oxidation of propane with a molecular oxygen-containing gas.
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:
The present invention provides an improved process for production of acrylic acid by subjecting propylene and/or acrolein to catalytic gas-phase oxidation with a molecular oxygen-containing gas. In the process, the mixed gas obtained by the catalytic gas-phase oxidation is contacted with an aqueous collecting agent containing acrylic acid, acetic acid and a poorly-soluble-in-water solvent, to form an aqueous acrylic acid solution; and the aqueous acrylic acid solution is subjected to azeotropic distillation in the presence of a poorly-soluble-in-water solvent to remove by-products and obtain high-purity acrylic acid.
摘要:
Acrylic acid can be produced efficiently by subjecting acrolein to catalytic gas-phase oxidation in the presence of a molybdenum/vanadium-based oxide catalyst prepared by using particular substances as the raw materials of the individual metal elements constituting the catalyst. A preferable example of such a catalyst is prepared by using, as the raw materials of vanadium, ammonium metavanadate and at least one vanadium oxide in which the valency of vanadium is larger than 0 but smaller than 5; as the raw material of copper, copper nitrate; and, as at least part of the raw material(s) of antimony, at least one antimony oxide in which the valency of antimony is larger than 0 but smaller than 5.
摘要:
A process for the gas phase catalytic oxidation of a C.sub.3-6 alkane, alkanol, alkene or alkenal using as a catalyst multimetal oxide compositions of the formula I, [X.sup.1.sub.a X.sup.2.sub.b O.sub.x ].sub.p [X.sup.3.sub.c X.sup.4.sub.d X.sup.5.sub.e X.sup.6.sub.f X.sup.7.sub.g X.sup.2.sub.h O.sub.y ].sub.q, where X.sup.1 is bismuth, tellurium, antimony, tin and/or copper, X.sup.2 is molybdenum and/or tungsten, X.sup.3 is an alkali metal, thallium and/or samarium, X.sup.4 is an alkaline earth metal, nickel, cobalt, copper, manganose, zinc, tin, cadmium and/or mercury, X.sup.6 is iron, chromium, cerium and/or vanadium, X.sup.6 is phosphorus, arsenic, boron and/or antimony, X.sup.7 is a rare-earth metal, titanium, zirconium, niobium, tantalum, rhenium, ruthenium, rhodium, silver, gold, aluminum, gallium, indium, silicon, geranium, lead, thorium and/or uranium, a is from 0.01 to 8, b is from 0.1 to 30, c is from 0 to 4, d is from 0 to 20, e is from 0 to 20, f is from 0 to 6, g is from 0 to 15, h is from 8 to 16, x and y are numbers determined by the valency and frequency of the elements in I other than oxygen, and p and q are numbers whose ratio p/q is from 0.1 to 10, containing three-dimensional regions with a chemical composition X.sup.1.sub.a X.sup.2.sub.b O.sub.x which are delimited from their local environment due to their chemical composition which is different from their local environment, and whose maximum diameter is from 1 to 25 .mu.m.