Abstract: The invention relates to a process for preparing butadiene from n-butenes, which comprises the following steps: A) provision of a feed gas stream a comprising n-butenes; B) introduction of the feed gas stream a comprising n-butenes and an oxygen-comprising gas into at least one dehydrogenation zone and oxidative dehydrogenation of n-butenes to butadiene, giving a product gas stream b comprising butadiene, unreacted n-butenes, water vapor, oxygen, low-boiling hydrocarbons, possibly carbon oxides and possibly inert gases; C) cooling and compression of the product gas stream b in at least one cooling stage and at least one compression stage, with the product gas stream b being brought into contact with a circulated coolant to give at least one condensate stream c1 comprising water and a gas stream c2 comprising butadiene, n-butenes, water vapor, oxygen, low-boiling hydrocarbons, possibly carbon oxides and possibly inert gases; D) separation of incondensable and low-boiling gas constituents comprising oxygen,

Abstract: The invention relates to a process for preparing butadiene from n-butenes, which comprises the steps: A) provision of a feed gas stream a comprising n-butenes; B) introduction of the feed gas stream a comprising n-butenes and an oxygen-comprising gas into at least one oxidative dehydrogenation zone and oxidative dehydrogenation of n-butenes to butadiene, giving a product gas stream b comprising butadiene, unreacted n-butenes, water vapor, oxygen, low-boiling hydrocarbons, high-boiling secondary components, possibly carbon oxides and possibly inert gases; Ca) cooling of the product gas stream b by contacting with an organic solvent as coolant, Cb) compression of the product gas stream b in at least one compression stage, giving at least one aqueous condensate stream c1 and a gas stream c2 comprising butadiene, n-butenes, water vapor, oxygen, low-boiling hydrocarbons, possibly carbon oxides and possibly inert gases; D) separation of incondensable and low-boiling gas constituents comprising oxygen, low-boiling

Abstract: The invention relates to a catalyst which comprises a catalytically active multimetal oxide which comprises molybdenum and at least one further metal has the general formula (I) Mo12BiaMnbCocFedX1eX2fOx??(I), where the variables have the following meanings: X1=Si and/or Al; X2=Li, Na, K, Cs and/or Rb; a=0.2 to 1; b=0 to 2; c=2 to 10; d=0.5 to 10; e=0 to 10; f=0 to 0.5; and x=is a number determined by the valence and abundance of the elements other than oxygen in (I).

Abstract: The invention relates to a catalyst, in particular a coated catalyst, for the oxidative dehydrogenation of n-butenes to butadiene, its use and also a process for the oxidative dehydrogenation of n-butenes to butadiene.

Abstract: The invention relates to a process for the oxidative dehydrogenation of n-butenes to butadiene, which comprises at least two production steps (i) and at least one regeneration step (ii), in which (i) in one production step, a starting gas mixture comprising n-butenes is mixed with an oxygen-comprising gas and brought into contact with a multimetal oxide catalyst which comprises at least molybdenum and a further metal and is arranged in a fixed catalyst bed in a fixed-bed reactor, and (ii) in a regeneration step, the multimetal oxide catalyst is regenerated by passing an oxygen-comprising regeneration gas mixture over the fixed catalyst bed and burning off the carbon deposited on the catalyst, where a regeneration step (ii) is carried out between two production steps (i), wherein the at least two production steps (i) are carried out at a temperature of at least 350° C. and the at least one regeneration step (ii) is carried out at a temperature which is not more than 50° C.

Abstract: The invention relates to a process for the oxidative dehydrogenation of n-butenes to butadiene, which comprises two or more production steps (i) and at least one regeneration step (ii), in which (i) in one production step, a starting gas mixture comprising n-butenes is mixed with an oxygen-comprising gas and brought into contact with a multimetal oxide catalyst which comprises at least molybdenum and a further metal and is arranged in a fixed catalyst bed in a fixed-bed reactor at a temperature of from 220 to 490° C., and, before the relative decrease in conversion at constant temperature is >25%, (ii) in a regeneration step, the multimetal oxide catalyst is regenerated by passing an oxygen-comprising regeneration gas mixture at a temperature of from 200 to 450° C.

Abstract: The invention relates to a coated catalyst which comprises (a) a support body, (b) a shell comprising a catalytically active multimetal oxide comprising molybdenum and at least one further metal, where the shell is made up of multimetal oxide particles having a d50 of from 6 to 13 ?m, and can be obtained by (i) production of a multimetal oxide precursor composition comprising molybdenum and at least one further metal, (ii) production of a shaped body from the multimetal oxide precursor composition, (iii) calcination of the shaped body composed of the multimetal oxide precursor composition to produce a multimetal oxide composition, (iv) milling of the shaped body composed of multimetal oxide composition to form multimetal oxide particles having a d50 of from 6 to 13 ?m, (v) coating of the support body with the multimetal oxide particles, (vi) thermal treatment of the coated support body.

Abstract: Catalysts comprising: a ground, spent (de)hydrogenation catalyst material present in an amount of 10 to 70% by weight based on the catalyst, the ground, spent catalyst material comprising iron oxide; and a fresh catalyst material present in an amount of 30 to 90% by weight based on the catalyst, the fresh catalyst material comprising iron oxide, wherein at least a portion of the iron oxide in the fresh catalyst material comprises a phase selected from the group consisting of hematite, potassium ferrite, and mixtures thereof are described along with processes for preparing and using the same.

Abstract: The present invention relates to a process for producing propylene oxide comprising (I) reacting propene with hydrogen peroxide in the presence of a catalyst to give a mixture (GI) comprising propylene oxide, unreacted propene, and oxygen; (II) separating propylene oxide from mixture (GI) to give a mixture (GII) comprising propene and oxygen; (III) reducing the oxygen comprised in mixture (GII) at least partially by reaction with hydrogen in the presence of a catalyst comprising Sn and at least one noble metal.

Abstract: The invention relates to a reactor and a process for preparing chlorine from hydrogen chloride by gas-phase oxidation by means of oxygen in the presence of a heterogeneous catalyst in a fluidized bed, with gas-permeable plates being located in the fluidized bed. The gas-permeable plates are connected in a thermally conductive manner to a heat exchanger located in the fluidized bed.

Abstract: The present invention relates to a catalytically active composition comprising as active component Pd and Bi and at least one element selected from the group (a) consisting of Rh, Au, Sb, V, Cr, W, Mn, Fe, Co, Ni, Na, Cs and Ba, or Pd, Rh and Bi and optionally an element selected from the group (a?) consisting of Au, Sb, V, Cr, W, Mn, Fe, Co, Ni, Pt, Cu, Ag, Na, Cs, Mg, Ca and Ba. The present invention further provides a process for dehydrogenating hydrocarbons, preferably oxo-functionalized hydrocarbons such as cyclopentanone, cyclohexanone and isovaleraldehyde, using the catalytically active composition.

Abstract: The present invention relates to a process for preparing optically active aldehydes or ketones which have from 3 to 25 carbon atoms and at least one racemizable stereocenter by catalytic dehydrogenation of the corresponding optically active primary or secondary alcohols in the gas phase in the presence of a catalyst.

Abstract: A catalyst for the oxidation of hydrogen in a process for the dehydrogenation of hydrocarbons, wherein the catalyst comprises, supported on ?-aluminum oxide, from 0.01 to 0.1% by weight of platinum and from 0.01 to 0.1% by weight of tin, based on the total weight of the catalyst, a process for the oxidation of hydrogen and a process for the dehydrogenation of hydrocarbons with an integrated oxidation process using the catalyst described.

Abstract: Catalysts comprising: a ground, spent (de)hydrogenation catalyst material present in an amount of 10 to 70% by weight based on the catalyst, the ground, spent catalyst material comprising iron oxide; and a fresh catalyst material present in an amount of 30 to 90% by weight based on the catalyst, the fresh catalyst material comprising iron oxide, wherein at least a portion of the iron oxide in the fresh catalyst material comprises a phase selected from the group consisting of hematite, potassium ferrite, and mixtures thereof are described along with processes for preparing and using the same.

Abstract: The present invention relates to a process for producing propylene oxide comprising (I) reacting propene with hydrogen peroxide in the presence of a catalyst to give a mixture (GI) comprising propylene oxide, unreacted propene, and oxygen; (II) separating propylene oxide from mixture (GI) to give a mixture (GII) comprising propene and oxygen; (III) reducing the oxygen comprised in mixture (GII) at least partially by reaction with hydrogen in the presence of a catalyst comprising Sn and at least one noble metal.

Abstract: Novel catalyst beds comprising a physical mixture of catalytically active and catalytically inactive shaped bodies, in which the catalytically inactive shaped bodies have rounded edges on the external rubbing surfaces.

Abstract: Process for preparing alpha, beta-unsaturated acyclic or cyclic carbonyl compounds by dehydrogenation of the corresponding saturated carbonyl compounds in the gas phase over a heterogeneous dehydrogenation catalyst comprising platinum and/or palladium and tin on an oxidic support.

Abstract: The invention relates to a process for carrying out exothermic chemical equilibrium reactions in a fluidized-bed reactor, wherein there is a temperature distribution in the fluidized bed of the fluidized-bed reactor and the temperature difference between the lowest temperature and the highest temperature is at least 10 K. The invention further relates to a fluidized-bed reactor for carrying out chemical reactions in a fluidized bed (5), wherein at least one heat exchanger (12, 28) is located in the fluidized bed (5) to control the temperature distribution.

Abstract: The present invention relates to a process for preparing optically active aldehydes or ketones which have from 3 to 25 carbon atoms and at least one racemizable stereocenter by catalytic dehydrogenation of the corresponding optically active primary or secondary alcohols in the gas phase in the presence of a catalyst.

Abstract: The invention relates to a reactor and a process for preparing chlorine from hydrogen chloride by gas-phase oxidation by means of oxygen in the presence of a heterogeneous catalyst in a fluidized bed, with gas-permeable plates being located in the fluidized bed. The gas-permeable plates are connected in a thermally conductive manner to a heat exchanger located in the fluidized bed.