Process for preparing ethene

Abstract

A process for the production of ethene by the vapour phased chemical dehydration of a feed comprising ethanol, water and ethoxyethane in a reactor at elevated temperature and pressure in the presence of a bed of catalyst comprising a supported heteropolytungstic acid characterised in that the reactor is maintained or configured so that it operates in a regime which satisfies the following parameters: 0.05<(Pwater/Pethanol+Pethoxyethane))/(8×10−5×GHSV+0.75) (1) and −20<Treaction−Tdew point−40×Ptotal feed+40×Pinerts<+80 (2) wherein Pwater, Pethanol and Pethoxyethane are respectively the partial pressures of water, ethanol and ethoxyethane in the thermodynamic equilibrium composition of the feed at the operating temperature and pressure of the process (in MPa), GHSV is the gas hourly space velocity of feed over the catalyst in hr−1, Treaction is the temperature of reaction in ° C., Tdewpoint is the dew point temperature of the feed at its thermodynamic equilibrium composition in 0 C, Ptotai feed is the total pressure of feed (in MPa) and Pinerts is the partial pressure of inerts in the feed (in MPa).

Dependencies are inferred from the claim text.