PURPOSE: To solve the problem of oxidation bleaching treatment in a recovering process and to improve the preservability, especially the heat and moisture resistances of a molded body produced by reutilizing recovered lower fatty acid ester of cellulose.

CONSTITUTION: A molded body of lower fatty acid ester of cellulose contg. org. foreign matter is immersed in an aq. soln. of a peroxide or an oxidized halogen compd. to remove the foreign matter from the molded body, this molded body and an epoxy compd. are dissolved in an org. solvent and a molded body is produced from the resulting dope. The molded body of lower fatty acid ester of cellulose contg. org. foreign matter is reutilized.