PURPOSE: To obtain a purified olefin capable of providing a polyolefin in high yield by industrially advantageously purifying ethylene or propylene for polymerization, especially that obtained by the fluid catalytic cracking of a heavy oil according to a new method.
CONSTITUTION: This method for purifying an olefin for polymerization is to bring ethylene or propylene into contact with a substance carrying an alkali metal, preferably by a method for passing the dried ethylene or propylene in a gaseous or a liquid state through a column filled with the substance carrying the alkali metal. A substance prepared by melting metallic sodium and supporting the molten sodium on a carrier is preferred as the substance carrying the alkali metal. Potassium carbonate, active carbon, etc., are preferred as the carrier and the average particle diameter thereof is preferably 1-10mm. The ethylene or propylene is preferably brought into contact with the substance carrying the alkali metal at 10-80°C.
YASUDA KAZUO
SHIMONISHI SHOGO
