摘要:
The present invention relates to the use of a catalyst comprising at least one first catalyst zone located towards the gas inlet, a second catalyst zone located closer to the gas outlet and a third catalyst zone located even closer to or at the gas outlet for the preparation of phthalic anhydride by gas-phase oxidation of o-xylene and/or naphthalene, with the catalyst zones preferably each having an active composition comprising TiO2, characterized in that the catalyst activity of the first catalyst zone is higher than the catalyst activity of the second catalyst zone. Furthermore, a preferred process for the preparation of phthalic anhydride is described.
摘要:
The present invention relates to processes for improving or optimizing a catalyst for the preparation of phthalic anhydride by gas-phase oxidation of o-xylene and/or napthalene, which comprises the following steps: a) provision of a starting catalyst (C) comprising at least one first catalyst zone located towards the gas inlet and a second catalyst zone located closer to the gas outlet, with the catalyst zones preferably each having an active composition comprising TiO2; b) replacement of part of the first catalyst zone by an upstream zone of a catalyst having a higher activity than the first catalyst zone in order to provide an improved catalyst. Furthermore, an improved catalyst obtainable by this process is described.
摘要:
The present invention relates to the use of a catalyst comprising at least one first catalyst zone located towards the gas inlet, a second catalyst zone located closer to the gas outlet and a third catalyst zone located even closer to or at the gas outlet for the preparation of phthalic anhydride by gas-phase oxidation of o-xylene and/or naphthalene, with the catalyst zones preferably each having an active composition comprising TiO2, characterized in that the catalyst activity of the first catalyst zone is higher than the catalyst activity of the second catalyst zone. Furthermore, a preferred process for the preparation of phthalic anhydride is described.
摘要:
The present invention relates to processes for improving or optimizing a catalyst for the preparation of phthalic anhydride by gas-phase oxidation of o-xylene and/or naphthalene, which comprises the following steps: a) provision of a starting catalyst (C) comprising at least one first catalyst zone located towards the gas inlet and a second catalyst zone located closer to the gas outlet, with the catalyst zones preferably each having an active composition comprising TiO2; b) replacement of part of the first catalyst zone by an upstream zone of a catalyst having a higher activity than the first catalyst zone in order to provide an improved catalyst. Furthermore, an improved catalyst obtainable by this process is described.
摘要:
The present invention relates to the use of titanium dioxide having a content of sulphur, calculated as elemental sulphur, of less than about 1000 ppm and a BET surface area of at least 5 m2/g for preparing a catalyst for gas phase oxidation of hydrocarbons, especially for gas phase oxidation of o-xylene and/or naphthalene. Also described is a preferred process for preparing such a catalyst.
摘要:
The present invention relates to a catalyst for preparing phthalic anhydride by gas phase oxidation of o-xylene and/or naphthalene, comprising at least three catalyst zones which have different compositions and, from the gas inlet side toward the gas outlet side, are referred to as first, second and third catalyst zone, the catalyst zones having in each case an active composition comprising TiO2 with a content of Na of less than 0.3% by weight, and the active composition content decreasing from the first catalyst zone disposed toward the gas inlet side to the third catalyst zone disposed toward the gas outlet side, with the proviso that (a) the first catalyst zone has an active composition content between about 7 and 12% by weight, (b) the second catalyst zone has an active composition content in the range between 6 and 11% by weight, the active composition content of the second catalyst zone being less than or equal to the active composition content of the first catalyst zone, and (c) the third catalyst zone has an active composition content in the range between 5 and 10% by weight, the active composition content of the third catalyst zone being less than or equal to the active composition content of the second catalyst zone. Also described is a preferred process for preparing such a catalyst and the preferred use of the titanium dioxide used in accordance with the invention.
摘要:
The present invention relates to a catalyst for preparing phthalic anhydride by gas phase oxidation of o-xylene and/or naphthalene, comprising at least three catalyst zones which have different compositions and, from the gas inlet side toward the gas outlet side, are referred to as first, second and third catalyst zone, the catalyst zones having in each case an active composition comprising TiO2, and the active composition content decreasing from the first catalyst zone disposed toward the gas inlet side to the third catalyst zone disposed toward the gas outlet side, with the proviso that (a) the first catalyst zone has an active composition content between about 7 and 12% by weight, (b) the second catalyst zone has an active composition content in the range between 6 and 11% by weight, the active composition content of the second catalyst zone being less than or equal to the active composition content of the first catalyst zone, and (c) the third catalyst zone has an active composition content in the range between 5 and 10% by weight, the active composition content of the third catalyst zone being less than or equal to the active composition content of the second catalyst zone. Also described is a preferred process for preparing such a catalyst and the preferred use of the titanium dioxide used in accordance with the invention.
摘要:
The invention relates to a coated catalyst, especially for oxidation of methanol to formaldehyde, which, on an inert, preferably essentially nonporous, support body, has at least one coating which comprises, before the removal of the organic fractions of components b) and c): (a) oxides, or precursor compounds convertible to the corresponding oxides, of molybdenum and iron, where the molar ratio of Mo:Fe is between 1:1 and 5:1, and optionally further metallic components or metal oxide components or precursor compounds convertible to the corresponding oxides, (b) at least one organic binder, preferably an aqueous dispersion of copolymers, especially selected from vinyl acetate/vinyl laurate, vinyl acetate/ethylene, vinyl acetate/acrylate, vinyl acetate/maleate, styrene/acrylate or mixtures thereof, and (c) at least one further component selected from the group consisting of SiO2 sol or precursors thereof, Al2O3 sol or precursors thereof, ZrO2 sol or precursors thereof, TiO2 sol or precursors thereof, waterglass, MgO, cement, monomeric, oligomeric or polymeric silanes, alkoxysilanes, aryloxysilanes, acryloyloxysilanes, aminosilanes, siloxanes or silanols. Additionally described is a process for preparing the catalyst and its preferred use.
摘要:
The present invention relates to a catalyst, in particular for the preparation of phthalic anhydride by gas phase oxidation of o-xylene and/or naphthalene, having an inert support and at least one layer which has been applied thereto and has a catalytically active composition comprising TiO2, characterized in that at least a portion of the TiO2 used has the following properties: (a) the BET surface area is more than 15 m2/g, (b) the primary crystal size is more than 210 ångstrøm. Also described is a preferred process for preparing such a catalyst, and the preferred use of the titanium dioxide used in accordance with the invention.
摘要翻译:本发明涉及一种催化剂,特别是用于通过邻二甲苯和/或萘的气相氧化制备邻苯二甲酸酐,其具有惰性载体和至少一层已被施加到其上并具有催化活性组合物,该组合物包含 TiO 2,其特征在于所用的TiO 2的至少一部分具有以下性质:(a)BET表面积大于15m 2 / g,(b)初晶结晶尺寸大于210μm。 还描述了制备这种催化剂的优选方法,以及根据本发明使用的二氧化钛的优选用途。
摘要:
The present invention relates to a catalyst, in particular for the preparation of phthalic anhydride by gas phase oxidation of o-xylene and/or naphthalene, having an inert support and at least one layer which has been applied thereto and has a catalytically active composition comprising TiO2, characterized in that at least a portion of the TiO2 used has the following properties: (a) the BET surface area is more than 15 m2/g, (b) the primary crystal size is more than 210 ångstrøm. Also described is a preferred process for preparing such a catalyst, and the preferred use of the titanium dioxide used in accordance with the invention.
摘要翻译:本发明涉及一种催化剂,特别是用于通过邻二甲苯和/或萘的气相氧化制备邻苯二甲酸酐,其具有惰性载体和至少一层已被施加到其上并具有催化活性组合物,该组合物包含 TiO 2 2,其特征在于所用的TiO 2的至少一部分具有以下性质:(a)BET表面积大于15μm2 SUP> / g,(b)初级晶体尺寸超过210østrstrøm。 还描述了制备这种催化剂的优选方法,以及根据本发明使用的二氧化钛的优选用途。