The present disclosure relates to a method for preparing a ceria-zirconia composite oxide, a ceria-zirconia composite oxide, and a catalyst including the same.

The present disclosure relates to a method for preparing a ceria-zirconia composite oxide, a ceria-zirconia composite oxide, and a catalyst including the same.

The present disclosure relates to a method for preparing a ceria-zirconia composite oxide, a ceria-zirconia composite oxide, and a catalyst including the same.

The invention relates to a process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream a comprising n-butenes, B) feeding the input gas stream a comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream b comprising butadiene, unconverted n-butenes, water vapor, oxygen, low-boiling hydrocarbons and high-boiling secondary components, with or without carbon oxides and with or without inert gases; Ca) cooling the product gas stream b by contacting with a cooling medium in at least one cooling zone, the cooling medium being at least partly recycled and having an aqueous phase and an organic phase, Cb) compressing the cooled product gas stream b which may have been depleted of high-boiling secondary components in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2 comprising butadiene, n-butenes, water vapor, oxygen and low-boiling hydrocarbons, with or without carbon oxides and with or without inert gases; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons, with or without carbon oxides and with or without inert gases, as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbons comprising butadiene and n-butenes in an absorbent, giving an absorbent stream laden with C.sub.4 hydrocarbons and the gas stream d2, and then desorbing the C.sub.4 hydrocarbons from the laden absorbent stream, giving a C.sub.4 product gas stream d1, E) separating the C.sub.4 product stream d1 by extractive distillation with a butadiene-selective solvent into a stream e1 comprising butadiene and the selective solvent and a stream e2 comprising n-butenes; F) distilling the stream e1 comprising butadiene and the selective solvent into a stream f1 consisting essentially of the selective solvent and a stream f2 comprising butadiene, wherein stage Cb) comprises at least two compression stages Cba) and at least two cooling stages Cbb) configured in the form of quench columns, the cooling in the cooling stages being effected by direct contacting with a biphasic cooling medium having an aqueous phase and an organic phase.

The invention relates to a process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream a comprising n-butenes, B) feeding the input gas stream a comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream b comprising butadiene, unconverted n-butenes, water vapor, oxygen, low-boiling hydrocarbons and high-boiling secondary components, with or without carbon oxides and with or without inert gases; Ca) cooling the product gas stream b by contacting with a cooling medium in at least one cooling zone, the cooling medium being at least partly recycled and having an aqueous phase and an organic phase, Cb) compressing the cooled product gas stream b which may have been depleted of high-boiling secondary components in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2 comprising butadiene, n-butenes, water vapor, oxygen and low-boiling hydrocarbons, with or without carbon oxides and with or without inert gases; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons, with or without carbon oxides and with or without inert gases, as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbons comprising butadiene and n-butenes in an absorbent, giving an absorbent stream laden with C.sub.4 hydrocarbons and the gas stream d2, and then desorbing the C.sub.4 hydrocarbons from the laden absorbent stream, giving a C.sub.4 product gas stream d1, E) separating the C.sub.4 product stream d1 by extractive distillation with a butadiene-selective solvent into a stream e1 comprising butadiene and the selective solvent and a stream e2 comprising n-butenes; F) distilling the stream e1 comprising butadiene and the selective solvent into a stream f1 consisting essentially of the selective solvent and a stream f2 comprising butadiene, wherein stage Cb) comprises at least two compression stages Cba) and at least two cooling stages Cbb) configured in the form of quench columns, the cooling in the cooling stages being effected by direct contacting with a biphasic cooling medium having an aqueous phase and an organic phase.

The present invention relates to a process for the dehydration of at least one oxygenated compound, preferably selected from saturated alcohols, unsaturated alcohols, diols, ethers, in the presence of at least one dehydration catalyst selected from cerium oxide (CeO.sub.2), aluminium oxide (γ-Al.sub.2O.sub.3), aluminium silicate, silica-aluminas (SiO.sub.2-Al.sub.2O.sub.3), aluminas, zeolites, sulfonated resins, ion-exchange resins, metal oxides (for example, lanthanum oxide, zirconium oxide, tungsten oxide, thallium oxide, magnesium oxide, zinc oxide); of at least one basic agent selected from ammonia (NH.sub.3), or from inorganic or organic compounds containing nitrogen capable of developing ammonia (NH.sub.3) during said dehydration process; and, optionally, of silica (SiO.sub.2), or of at least one catalyst for the dissociation of ammonia (NH.sub.3) selected from catalysts comprising silica (SiO.sub.2), preferably of silica (SiO.sub.2).

The present invention relates to a process for the dehydration of at least one oxygenated compound, preferably selected from saturated alcohols, unsaturated alcohols, diols, ethers, in the presence of at least one dehydration catalyst selected from cerium oxide (CeO.sub.2), aluminium oxide (γ-Al.sub.2O.sub.3), aluminium silicate, silica-aluminas (SiO.sub.2-Al.sub.2O.sub.3), aluminas, zeolites, sulfonated resins, ion-exchange resins, metal oxides (for example, lanthanum oxide, zirconium oxide, tungsten oxide, thallium oxide, magnesium oxide, zinc oxide); of at least one basic agent selected from ammonia (NH.sub.3), or from inorganic or organic compounds containing nitrogen capable of developing ammonia (NH.sub.3) during said dehydration process; and, optionally, of silica (SiO.sub.2), or of at least one catalyst for the dissociation of ammonia (NH.sub.3) selected from catalysts comprising silica (SiO.sub.2), preferably of silica (SiO.sub.2).

Process for the production of a diene, preferably a conjugated diene, more preferably 1,3-butadiene, comprising the dehydration of at least one alkenol in the presence of at least one catalytic material comprising at least one acid catalyst based on silica (SiO.sub.2) and alumina (AI.sub.2O.sub.3), preferably a silica-alumina (SiO.sub.2-AI.sub.2O.sub.3), said catalyst having a content of alumina (AI.sub.2O.sub.3) lower than or equal to 12% by weight, preferably ranging from 0.1% by weight to 10% by weight, with respect to the total weight of the catalyst. Preferably, said alkenol can be obtained directly from biosynthesis processes, or through the catalytic dehydration of at least one diol, preferably a butanediol, more preferably 1,3-butanediol, even more preferably bio-1,3-butanediol, deriving from biosynthesis processes. Preferably, said 1,3-butadiene is bio-1,3-butadiene.

Process for the production of a diene, preferably a conjugated diene, more preferably 1,3-butadiene, comprising the dehydration of at least one alkenol in the presence of at least one catalytic material comprising at least one acid catalyst based on silica (SiO.sub.2) and alumina (AI.sub.2O.sub.3), preferably a silica-alumina (SiO.sub.2-AI.sub.2O.sub.3), said catalyst having a content of alumina (AI.sub.2O.sub.3) lower than or equal to 12% by weight, preferably ranging from 0.1% by weight to 10% by weight, with respect to the total weight of the catalyst. Preferably, said alkenol can be obtained directly from biosynthesis processes, or through the catalytic dehydration of at least one diol, preferably a butanediol, more preferably 1,3-butanediol, even more preferably bio-1,3-butanediol, deriving from biosynthesis processes. Preferably, said 1,3-butadiene is bio-1,3-butadiene.

[1] A catalyst for synthesizing 1,3-butadiene by contact with ethanol, which comprises tungsten oxide and magnesium oxide. [2] The catalyst, wherein a mass ratio of the magnesium oxide to the tungsten oxide (magnesium oxide/tungsten oxide) is 0.1 to 200. [3] The catalyst, wherein the mass ratio is at least 5. [4] The catalyst, wherein amounts of the tungsten oxide and the magnesium oxide relative to 100% by mass of the catalyst are as follows: the amount of the tungsten oxide: 0.1 to 90% by mass; and the amount of the magnesium oxide: 10 to 90% by mass.