The present invention relates to a process for the production of -springene of formula (I) wherein a compound of formula (II) is heated in the presence of a catalyst.

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The present invention relates to a process for the production of -springene of formula (I) wherein a compound of formula (II) is heated in the presence of a catalyst.

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The present invention relates to a process for the production of -springene of formula (I) wherein a compound of formula (II) is heated in the presence of a catalyst.

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The invention relates to immobilized metal alkylidene catalysts. The catalysts are useful in olefin metathesis. ##STR00001##

The invention relates to immobilized metal alkylidene catalysts. The catalysts are useful in olefin metathesis. ##STR00001##

The invention relates to immobilized metal alkylidene catalysts. The catalysts are useful in olefin metathesis. ##STR00001##

The invention relates to a method for producing 1,3-butanediene from a butanediol feedstock that includes: a) A step for esterification of butanediol by a carboxylic acid to form the corresponding diester; b) A step for pyrolysis of the diester effluent obtained from step a); c) A step for distillation fed by at least the carboxylic acid effluent obtained from step a), and producing an aqueous distillate and a carboxylic acid residue; d) A step for drying the carboxylic acid that is fed at least by the carboxylic acid residue obtained from step c) and producing a water effluent and a carboxylic acid product that feeds step a).

The invention relates to a method for producing 1,3-butanediene from a butanediol feedstock that includes: a) A step for esterification of butanediol by a carboxylic acid to form the corresponding diester; b) A step for pyrolysis of the diester effluent obtained from step a); c) A step for distillation fed by at least the carboxylic acid effluent obtained from step a), and producing an aqueous distillate and a carboxylic acid residue; d) A step for drying the carboxylic acid that is fed at least by the carboxylic acid residue obtained from step c) and producing a water effluent and a carboxylic acid product that feeds step a).

The invention relates to a method for producing 1,3-butanediene from a butanediol feedstock that includes: a) A step for esterification of butanediol by a carboxylic acid to form the corresponding diester; b) A step for pyrolysis of the diester effluent obtained from step a); c) A step for distillation fed by at least the carboxylic acid effluent obtained from step a), and producing an aqueous distillate and a carboxylic acid residue; d) A step for drying the carboxylic acid that is fed at least by the carboxylic acid residue obtained from step c) and producing a water effluent and a carboxylic acid product that feeds step a).

The invention pertains to a method for converting butanediol into butadiene that is fed with a butanediol feedstock, where said method comprises at least an esterification step, a pyrolysis step, and a step for separation of the pyrolysis effluent comprising at least one section for cooling said pyrolysis effluent and producing a liquid pyrolysis effluent and a steam pyrolysis effluent and a gas-liquid washing section that is fed at the top with a fraction of the butanediol diester effluent obtained from the esterification step and at the bottom with the steam pyrolysis effluent, where said section produces a butadiene effluent at the top and a washing effluent at the bottom.