In the method of the present invention, 1,3-butadiene is produced by vaporizing an ethanol feedstock in a vaporizer (104), feeding the resulting into two or more parallel first reactors (108) to convert the ethanol to acetaldehyde in the presence of a first catalyst, supplying the resulting intermediate gas to a second reactor (110) to convert the ethanol and acetaldehyde to 1,3-butadiene in the presence of a second catalyst, purifying the resulting crude gas containing 1,3-butadiene by a gas-liquid separator (112), a first distillation column (114), a fourth reactor (116), a second distillation column (118), and mixing one of both of a part of the ethanol-containing gas and an acetaldehyde-containing gas obtained in the second distillation column (118) are mixed with the intermediate gas, thereby adjusting an ethanol/acetaldehyde molar ratio in the intermediate gas to 1 to 100.

In the method of the present invention, 1,3-butadiene is produced by vaporizing an ethanol feedstock in a vaporizer (104), feeding the resulting into two or more parallel first reactors (108) to convert the ethanol to acetaldehyde in the presence of a first catalyst, supplying the resulting intermediate gas to a second reactor (110) to convert the ethanol and acetaldehyde to 1,3-butadiene in the presence of a second catalyst, purifying the resulting crude gas containing 1,3-butadiene by a gas-liquid separator (112), a first distillation column (114), a fourth reactor (116), a second distillation column (118), and mixing one of both of a part of the ethanol-containing gas and an acetaldehyde-containing gas obtained in the second distillation column (118) are mixed with the intermediate gas, thereby adjusting an ethanol/acetaldehyde molar ratio in the intermediate gas to 1 to 100.

The method of the present invention for producing 1,3-butadiene includes: vaporizing an ethanol feedstock in a vaporizer (104), supplying the feedstock to two or more parallel first reactors (108) to convert ethanol into acetaldehyde in the presence of a first catalyst; supplying a resulting intermediate gas to a second reactor (110) to convert ethanol and acetaldehyde into 1,3-butadiene in the presence of a second catalyst; purifying a resulting crude gas containing 1,3-butadiene by a gas-liquid separator (112), a first distillation column (114), a fourth reactor (116), and a second distillation column (118); and supplying an oxygen-containing gas to at least one of the two or more parallel first reactors (108) under specific conditions, while discharging a carbon dioxide-containing gas from the first reactor (108), to thereby regenerate the first catalyst, while continuing the conversion reaction.

The method of the present invention for producing 1,3-butadiene includes: vaporizing an ethanol feedstock in a vaporizer (104), supplying the feedstock to two or more parallel first reactors (108) to convert ethanol into acetaldehyde in the presence of a first catalyst; supplying a resulting intermediate gas to a second reactor (110) to convert ethanol and acetaldehyde into 1,3-butadiene in the presence of a second catalyst; purifying a resulting crude gas containing 1,3-butadiene by a gas-liquid separator (112), a first distillation column (114), a fourth reactor (116), and a second distillation column (118); and supplying an oxygen-containing gas to at least one of the two or more parallel first reactors (108) under specific conditions, while discharging a carbon dioxide-containing gas from the first reactor (108), to thereby regenerate the first catalyst, while continuing the conversion reaction.

The present invention relates to a process for producing butadiene from ethanol, in two reaction steps, comprising a step a) of converting ethanol into acetaldehyde and a step b) of conversion into butadiene, said step b) simultaneously implementing a reaction step and a regeneration step in (n+n/2) fixed-bed reactors, n being equal to 2 or a multiple thereof, comprising a catalyst, said regeneration step comprising four successive regeneration phases, said step b) also implementing a regeneration loop for the inert gas and at least one regeneration loop for the gas streams comprising oxygen.

The present invention relates to a process for producing butadiene from ethanol, in two reaction steps, comprising a step a) of converting ethanol into acetaldehyde and a step b) of conversion into butadiene, said step b) simultaneously implementing a reaction step and a regeneration step in (n+n/2) fixed-bed reactors, n being equal to 2 or a multiple thereof, comprising a catalyst, said regeneration step comprising four successive regeneration phases, said step b) also implementing a regeneration loop for the inert gas and at least one regeneration loop for the gas streams comprising oxygen.

The present invention relates to a transition metal compound for an olefin polymerization catalyst, the transition metal compound being represented by chemical formula 1. The description of chemical formula 1 is as defined in the specification.

The present invention relates to a transition metal compound for an olefin polymerization catalyst, the transition metal compound being represented by chemical formula 1. The description of chemical formula 1 is as defined in the specification.

The present invention relates to a process for preparing an aromatic hydrocarbon, and processes for producing p-xylene and terephthalic acid. The process for producing said aromatic hydrocarbon comprises a step of contacting an olefin with a diene in the presence of a catalyst to produce an aromatic hydrocarbon, which is characterized in that, at least a part of said olefin is substituted with dienophile. The reaction pressure can be reduced and the xylene selectivity can be increased with the improvement of the present invention.

The invention relates to a process for the production of 1,3-butadiene from ethanol and acetaldehyde with catalyst regeneration comprising a) reacting a feed comprising ethanol and acetaldehyde in a reactor having at least one adiabatic reaction zone comprising a supported catalyst, and b) regenerating the supported catalyst. Regeneration stage b) comprises stripping step i. at a temperature of 300 to 400? C., ii. first and second combustion steps ii. and iii. at a temperature of 350 to 400? ? C. and 400 to 550? C. respectively, and stripping step iv. at a temperature of 550? C. to 300? ? C. The gas flows to each of regeneration steps b)i. to b)iv. are first heated and then contact the supported catalyst.