Acrylic Acid → Benzaldehyde

HRID 2251721Notes

Reaction equation

HRID 2251721 reaction equation
[OH2:1].NN.[C:4]1(NN)[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[C:12]([OH:16])(=[O:15])[CH:13]=[CH2:14]>>[C:12]([OH:16])(=[O:15])[CH:13]=[CH2:14].[CH:8](=[O:15])[C:7]1[O:1][CH:4]=[CH:5][CH:6]=1.[CH:12]([CH:13]=[CH2:14])=[O:15].[CH:12](=[O:15])[C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1

Participants

7

Reactant 3

HCID 6581Acrylic AcidHCID 7516PhenylhydrazineHCID 24654Hydrazine hydrate (1:1)

Product 4

HCID 240BenzaldehydeHCID 6581Acrylic AcidHCID 7362FurfuralHCID 7847Acrolein

Procedure

High purity acrylic acid can be obtained by distilling or crystallizing purified acrylic acid obtained from the high boiling point substance separation column 40 of FIG. 1. When distillation is performed, there can be used a method of adding, for example, the known primary amine such as hydrazine hydrate, phenylhydrazine and the like and/or a salt thereof together with purified acrylic acid to a distillation column at an amount of 1.0 to 10.0 mol, more preferably 1.0 to 5.0 mol relative to 1 mol of contained aldehyde, after adding the treating agent, performing distillation under reduced pressure and the like in a distillation column such as a flash column equipped with a mist separator under the conditions of a column top pressure of 10 to 150 hPa(abs.) and a column top temperature of 35 to 90° C. and the like. By this treatment, high purity acrylic acid having a content of aldehydes such as furfural, acrolein, benzaldehyde and the like of 10 weight ppm or smaller can be obtained. In addition, by crystallization using a crystallization device, equivalent high purity acrylic acid may be obtained. When a water-absorbing resin is produced from acrylic acid, since odor resulting from impurities contained in the acrylic acid or stimulation on a skin are not preferable in some utilities, it is preferable to use such the high purity acrylic acid.

Workup

  1. distillationby distilling
  2. customcrystallizing
  3. custompurified acrylic acid
  4. customobtained from the high boiling point substance separation column 40 of FIG. 1
  5. distillationWhen distillation
  6. additionafter adding the treating agent
  7. distillationdistillation under reduced pressure
  8. distillationthe like in a distillation column such as a flash column
  9. customequipped with a mist separator under the conditions of a column top pressure of 10 to 150 hPa(abs.)
  10. customa column top temperature of 35 to 90° C.

Sources & evidence

ORD record
ord-1ed40739a54a45f3bdedc167cb9ff588
Source dataset
uspto-grants-2008_01
Patent number
US07319168B2

Reaction notes

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