Abstract: A container in combination with a solution of phosphoenolpyruvic acid, the container comprising an outer bag comprising a polyvinyl chloride type resin and an inner bag comprising an alkali resistant resin, the inner bag having stored therein an aqueous solution of phosphoenolpyruvic acid or a salt thereof at a pH of 10 to 13. A method for storing an aqueous solution of phosphoenolpyruvic acid or a salt thereof at a pH of 10 to 13 in a container comprising an inner bag and an outer bag, the method comprising introducing and then storing an aqueous solution comprising phosphoenolpyruvic acid in the inner bag, the inner bag comprising an alkali resistant resin and the outer bag comprising a polyvinyl chloride type resin.

Abstract: Disclosed is a method for stabilizing an aqueous solution of phosphoenolpyruvic acid and its salt, which comprises placing the solution under the condition of pH 10 to 13.Disclosed is also a container for phosphoenolpyruvic acid, comprising an outer bag comprising a polyvinyl chloride type resin and an inner bag comprising an alkali resistant resin for storing an aqueous solution of phosphoenolpyruvic acid or its salt under the condition of pH 10 to 13 therein.According to the present invention, a method for stabilizing phosphoenolpyruvic acid in an aqueous solution and a container for housing the stabilized phosphoenolpyruvic acid accompanied therewith can be obtained.