This invention relates to a process for producing cyanoacetates using asparagine as a precursor to cyanoacetamide, a staring material to form the cyanoacetates.

This invention relates to a process for producing cyanoacetates using a cyanoacetamide as a precursor.

This invention relates to a process for producing cyanoacetates using a cyanoacetamide as a precursor.

This invention relates to a process for producing cyanoacetates using aspartic acid as a precursor.

This invention relates to a process for producing cyanoacetates using aspartic acid as a precursor.

The present invention relates to a method of producing an acrylonitrile dimer, the method including: feeding an acrylonitrile monomer, a nonpolar solvent, an alcohol solvent, and a phosphorus-based catalyst to a dimerization reactor to perform a dimerization reaction and reaction product to a distillation column; feeding the acrylonitrile monomer, the nonpolar solvent, and the alcohol solvent from the distillation column to the dimerization reactor; feeding an acrylonitrile dimer and the phosphorus-based catalyst from the distillation column to an extraction device; oxidizing the phosphorus-based catalyst by feeding water including an acid component to the extraction device to inactivate the phosphorus-based catalyst; and separating the inactivated phosphorus-based catalyst and the acrylonitrile dimer.

The present invention relates to a method of producing an acrylonitrile dimer, the method including: feeding an acrylonitrile monomer, a nonpolar solvent, an alcohol solvent, and a phosphorus-based catalyst to a dimerization reactor to perform a dimerization reaction and reaction product to a distillation column; feeding the acrylonitrile monomer, the nonpolar solvent, and the alcohol solvent from the distillation column to the dimerization reactor; feeding an acrylonitrile dimer and the phosphorus-based catalyst from the distillation column to an extraction device; oxidizing the phosphorus-based catalyst by feeding water including an acid component to the extraction device to inactivate the phosphorus-based catalyst; and separating the inactivated phosphorus-based catalyst and the acrylonitrile dimer.

The present invention relates to a method of producing an acrylonitrile dimer, the method including: feeding an acrylonitrile monomer, a nonpolar solvent, an alcohol solvent, and a phosphorus-based catalyst to a dimerization reactor to perform a dimerization reaction and reaction product to a distillation column; feeding the acrylonitrile monomer, the nonpolar solvent, and the alcohol solvent from the distillation column to the dimerization reactor; feeding an acrylonitrile dimer and the phosphorus-based catalyst from the distillation column to an extraction device; oxidizing the phosphorus-based catalyst by feeding water including an acid component to the extraction device to inactivate the phosphorus-based catalyst; and separating the inactivated phosphorus-based catalyst and the acrylonitrile dimer.

The object is to prevent deterioration and loss of dicyanobenzene in producing dicyanobenzene by ammoxidation of xylene to thereby achieve industrial and economical advantage in producing of dicyanobenzene. The method for producing dicyanobenzene of the present invention includes: contacting a xylene-ammoxidation reaction gas containing dicyanobenzene in ammoxidation of xylene with an organic solvent so as to obtain a dicyanobenzene-absorbing solution; contacting the dicyanobenzene-absorbing solution with a basic aqueous solution containing a salt such as ammonium carbonate so as to extract a water-soluble salt formed by neutralization reaction between carboxylic acid in the dicyanobenzene-absorbing solution and a base in the basic aqueous solution into an aqueous phase; separating the mixture of the dicyanobenzene-absorbing solution and the basic aqueous solution into an organic phase and an aqueous phase; decomposing the salt such as ammonium carbonate contained in the organic phase for separation of the salt from the organic phase; and distilling the organic phase to separate low boiling point compounds contained in the organic phase from the organic phase so as to obtain dicyanobenzene.

The object is to prevent deterioration and loss of dicyanobenzene in producing dicyanobenzene by ammoxidation of xylene to thereby achieve industrial and economical advantage in producing of dicyanobenzene. The method for producing dicyanobenzene of the present invention includes: contacting a xylene-ammoxidation reaction gas containing dicyanobenzene in ammoxidation of xylene with an organic solvent so as to obtain a dicyanobenzene-absorbing solution; contacting the dicyanobenzene-absorbing solution with a basic aqueous solution containing a salt such as ammonium carbonate so as to extract a water-soluble salt formed by neutralization reaction between carboxylic acid in the dicyanobenzene-absorbing solution and a base in the basic aqueous solution into an aqueous phase; separating the mixture of the dicyanobenzene-absorbing solution and the basic aqueous solution into an organic phase and an aqueous phase; decomposing the salt such as ammonium carbonate contained in the organic phase for separation of the salt from the organic phase; and distilling the organic phase to separate low boiling point compounds contained in the organic phase from the organic phase so as to obtain dicyanobenzene.