Process for producing propylene

Abstract

Process for producing propylene from a propanol feedstock Aby reacting the propanol feedstock Ain a vapor phase dehydration reactor wherein the propanol is convened at a temperature comprised between 160 and 270° C. and at a pressure of above 0.1 MPa but less than 4.5 MPa, into a product stream Bcontaining propylene, propyl ethers, water and unconverted and/or isomerized propanols, cooling the product stream B, disengaging the cooled product stream Bin a separation unit to give a first stream Ccontaining propylene and propyl ethers, and a second product stream Dcontaining water, propyl ethers and unconverted and/or isomerized propanols, feeding the product stream Dto a dewatering unit wherein the water stream Fis separated from the propyl ethers and unconverted and/or isomerised propanols stream E, recycling the stream Einto the dehydration reactor, cooling the product stream C, feeding the cooled product stream Cto a purification unit wherein the propyl ethers stream Gis separated from the propylene stream H, and optionally, recycling the propyl ethers stream Gto either the dewatering unit or directly to dehydration reactor.