Method for decomposing cured epoxy resin

Abstract

There is provided a method for decomposing a cured epoxy resin, the method being capable of decomposing a cured epoxy resin containing silica efficiently. A cured epoxy resin containing silica is decomposed by being brought into contact with subcritical water including at least one alkaline compound selected from an alkaline metal salt and an alkaline metal hydroxide.

1 . A method for recovering a metal from a metal-containing product that the metal is encapsulated with a cured epoxy resin containing silica,
 the method comprising: bringing the cured epoxy resin containing silica into contact with subcritical water to decompose the resin, the subcritical water including an alkaline metal hydroxide as an alkaline compound.   
     
     
         2 . The method for recovering a metal from a metal-containing product of  claim 1 , wherein the amount of the alkaline compound added is 0.2 parts by weight or more relative to 1 part by weight of the cured epoxy resin. 
     
     
         3 . The method for recovering a metal from a metal-containing product of  claim 1 , wherein the alkaline metal hydroxide is sodium hydroxide or potassium hydroxide. 
     
     
         4 . The method for recovering a metal from a metal-containing product of  claim 1 , wherein the cured epoxy resin is brought into contact with subcritical water of 200 to 350° C. 
     
     
         5 . The method for recovering a metal from a metal-containing product of  claim 1 , wherein the duration of the contact of the cured epoxy resin to subcritical water is 2 to 6 hours.