Abstract: A process for producing propylene, which including feeding at least one of dimethyl ether and methanol to a reactor to be reacted in the presence of a catalyst; supplying an obtained reaction product to a separator by which low-boiling compounds having a boiling point of ?50° C. or lower at atmospheric pressure among the reaction product are separated; and recycling a proportion of at least 70% of a total amount of the separated low-boiling compounds to said reactor.

Abstract: There is provided a method for producing a raw gas for ammonia synthesis in which light hydrocarbons from a tube 3, steam from a tube 6 and oxygen-enriched air having an oxygen concentration of 40 to 60% by volume from an oxygen-enriched air supply source 7 are heated and are then introduced to a one-step reforming reactor 5 to thereby carry out a steam reforming reaction and an air partial oxidation reaction at the same time, and the resultant is subsequently passed through a shift reactor 12, a decarbonating device 14 and a methanation reactor 16 to remove carbon monoxide and carbon dioxide, thereby yielding a raw gas suitable for ammonia synthesis having a hydrogen to nitrogen molar ratio of about 3:1.

Abstract: A method for producing propylene including: transferring a feed gas including dimethyl ether and/or methanol and C4 and/or C5 olefins into a reactor, and reacting the feed gas in the presence of a catalyst, the feed gas prior to transferring into the reactor having a (supplied C4 and/or C5 olefins)/(supplied dimethyl ether and methanol) ratio of 0.25 to 7.5, in terms of the molar ratio based on the number of carbon atoms, and the feed gas being contacted with the catalyst at 350° C. to 600° C.; and an apparatus for producing propylene including: a hydrogenation reactor in which alkynes and/or dienes contained in C4 and/or C5 hydrocarbons is partially hydrogenated to be converted into an olefin having one double bond; a reactor in which C4 and/or C5 hydrocarbons is reacted with dimethyl ether and/or methanol in the presence of a catalyst; and a separator for separating propylene from the reaction product.

Abstract: A process for producing propylene, which including feeding at least one of dimethyl ether and methanol to a reactor to be reacted in the presence of a catalyst; supplying an obtained reaction product to a separator by which low-boiling compounds having a boiling point of ?50° C. or lower at atmospheric pressure among the reaction product are separated; and recycling a proportion of at least 70% of a total amount of the separated low-boiling compounds to said reactor.