Title:
CLEANING OF PHOSPHORIC ESTER
Document Type and Number:
Japanese Patent JP3655012
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain a purified phosphoric ester in high yield without discharging cloudy wastewater at all by adding a necessary component to the wastewater produced by rinsing and reusing the resultant wastewater as wash water.
SOLUTION: A cleaning step for extracting and separating a metal in the aqueous phase with wash water without forming an emulsion with a phosphoric ester and a rinsing step for rinsing the metal and chlorine components contained in water remaining together with the phosphoric ester phase are carried out when reacting phosphorus oxychloride with a dihydric phenol and a monohydric phenol in the presence of a metallic chloride catalyst and then removing the catalyst metal and chlorine components from the resultant aryl phosphate oligomer. Wastewater produced in the rinsing step is reused as wash water. Acidic water at pH≤2.6 or wash water containing a hydrogenphosphate soluble in water at ≤0.3mol/L concentration or alkaline water at pH≥12.5 is preferred as the wash water. Thereby, the metallic component derived from the catalyst can be removed without deteriorating the yield of the product.
Inventors:
Kazuhiro Matsubara
Haruyuki Minoura
Haruyuki Minoura
Application Number:
JP16946996A
Publication Date:
June 02, 2005
Filing Date:
June 28, 1996
Export Citation:
Assignee:
Asahi Kasei Chemicals Corporation
International Classes:
B01J27/138; C07F9/09; C08G79/02; C08G79/04; (IPC1-7): C08G79/04; B01J27/138; C07F9/09
Domestic Patent References:
| JP10017582A | ||||
| JP10007689A | ||||
| JP9192506A | ||||
| JP8176163A | ||||
| JP8027171A | ||||
| JP5001079A |
Attorney, Agent or Firm:
Kazuo Watanabe
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