Abstract:
The present invention relates to a method for the production of hydroformylation products from olefins having at least four carbon atoms. A high amount of the linear Ci-olefins with terminal double bonds that are present in the inlet comprising olefins, and also of the linear Ci-olefins having internal double bonds are converted to hydroformylation products. The invention further relates to a method for the production of 2-propylheptanol, comprising said hydroformylation method.
Abstract:
The invention relates to a method for producing phthalic anhydride by catalytic gas phase oxidation of o-xylol. According to said method, a gaseous mixture of o-xylol and an oxygen-containing gas is guided through at least two reaction zones in a main reactor, the temperature of said reaction zones being adjustable independently of each other, and is reacted to give a gaseous intermediate reaction product which contains unreacted o-xylol, phthalic anhydride reaction products with a lower oxidation state and phthalic anhydride, and the intermediate reaction product is introduced into a secondary reactor. The temperature in the reaction zones in the primary reactor is controlled in such a manner that the concentration of the unreacted o-xylol in the intermediate reaction product is at least 0.5% by weight. The method according to the invention allows an increase in total yield of phthalic anhydride without any or without substantial decrease in product quality.
Abstract:
The invention relates to a method for the continuous production of aldehydes comprising between 5 and 21 carbon atoms, by the isomerising hydroformylation in a homogenous phase of olefin compositions comprising between 4 and 20 carbon atoms and containing α-olefins and olefins with internal double bonds, by means of a synthesis gas, in the presence of a homogeneous rhodium catalyst that is complexed with an organophosphorus ligand containing oxygen atoms and/or nitrogen atoms and a free ligand. Said production is carried out at high temperature and high pressure in a multi-stage reaction system consisting of at least two reaction zones. According to said method, the olefin composition is first reacted in a first reaction zone or a group of several first reaction zones at a total pressure of between 10 and 40 bar, using a synthesis gas with a CO/H2 molar ratio of between 4:1 and 1:2 until a 40 to 95 % conversion of the α-olefins is obtained. The hydroformylation product from the first reaction zone or group of several first reaction zones is then reacted in a subsequent reaction zone or group of several reaction zones at a total pressure of between 5 and 30 bar, using a synthesis gas with a CO/H2 molar ratio of between 1:4 and 1:1000. The total pressure in the subsequent reaction zone or zones is respectively 1 to (G1-Gf) bar lower than that of the preceding reaction zone, whereby G1 represents the total pressure in the respective preceding reaction zone and Gf represents the total pressure in the respective reaction zone that succeeds said first reaction zone or zones, with the proviso that the difference between G1 and Gf is greater than 1 bar and the partial CO pressure in the subsequent reaction zone or zones is respectively lower than that of the preceding reaction zone.
Abstract:
The invention relates to phosphacyclohexanes of general formulae I and II, wherein the following designations, among others, apply: R can represent hydrogen, C1-100-alkyl, C7-20-aralkyl, C7-20-alkaryl, and C6-12-aryl; R to R can independently represent hydrogen, C1-20-alkyl, C7-20-aralkyl, C7-20-alkaryl, and C6-12-aryl; W, W' can independently represent single bonds or bridges comprising 1 to 20 carbon atoms, which can form part of a cyclic or aromatic group and can be interrupted by heteroatoms. Said phosphacyclohexanes are used as ligands in transition metal complexes of transition metals belonging to subgroup VIII of the periodic table.
Abstract:
The invention relates to a method for producing phthalic anhydride by catalytic gas phase oxidation of o-xylol. According to said method, a gaseous mixture of o-xylol and an oxygen-containing gas is guided through at least two reaction zones in a main reactor, the temperature of said reaction zones being adjustable independently of each other, and is reacted to give a gaseous intermediate reaction product which contains unreacted o-xylol, phthalic anhydride reaction products with a lower oxidation state and phthalic anhydride, and the intermediate reaction product is introduced into a secondary reactor. The temperature in the reaction zones in the primary reactor is controlled in such a manner that the concentration of the unreacted o-xylol in the intermediate reaction product is at least 0.5% by weight. The method according to the invention allows an increase in total yield of phthalic anhydride without any or without substantial decrease in product quality.
Abstract:
The invention relates to a method for starting a gas phase oxide reactor that contains a bed of a first catalyst, the active mass thereof containing a catalytically active silver vanadium oxide bronze, and at least one bed of a second catalyst, the catalytically active mass thereof containing vanadium pentoxide and titanium dioxide, and said reactor can be tempered by means of a heat transfer medium. In the operational mode, a gas flow that contains a charge C op of a hydrocarbon and molecular oxygen passes through the reactor via the bed of the first and the second catalyst, the heat transfer medium being at a temperature T op . In order to start, a) a gas flow containing an initial charge C o that is lower than C op is guided through the reactor at an initial temperature T o of the heat transfer medium that is lower than T op and b) the temperature of the heat transfer medium is brought to T op and the charge of the gas flow is brought to C op . Said method combines a short starting time without exceeding emission or quality specifications, with a long catalyst service life, a high yield and a low formation of axillary products.
Abstract:
The invention relates to a method for producing phthalic anhydride by catalytic gas phase oxidation of o-xylol. According to said method, a gaseous mixture of o-xylol and an oxygen-containing gas is reacted in a primary reactor to give a gaseous intermediate reaction product which contains unreacted o-xylol, phthalic anhydride reaction products with a lower oxidation state and phthalic anhydride, the reaction heat produced in the primary reactor being at least partially carried off by indirect cooling with a heat exchange medium, and introducing the intermediate reaction product to a secondary reactor. The concentration of the unreacted o-xylol in the intermediate reaction product is at least 1% by weight, and the sum of the concentrations of phthalic anhydride of the lower oxidation state in the intermediate reaction product is at least 0.5% by weight. The method according to the invention allows an increase in total yield of phthalic anhydride without any or without substantial decrease in product quality.
Abstract:
The invention relates to a method for producing phthalic anhydride by catalytic gas phase oxidation of o-xylol. According to said method, a gaseous mixture of o-xylol and an oxygen-containing gas is reacted in a primary reactor to give a gaseous intermediate reaction product which contains unreacted o-xylol, phthalic anhydride reaction products with a lower oxidation state and phthalic anhydride, the reaction heat produced in the primary reactor being at least partially carried off by indirect cooling with a heat exchange medium, and introducing the intermediate reaction product to a secondary reactor. The concentration of the unreacted o-xylol in the intermediate reaction product is at least 1% by weight, and the sum of the concentrations of phthalic anhydride of the lower oxidation state in the intermediate reaction product is at least 0.5% by weight. The method according to the invention allows an increase in total yield of phthalic anhydride without any or without substantial decrease in product quality.