摘要 |
A process for the preparation of an alkene from an oxygenate comprising contacting a reactant feedstream comprising at least one oxygenate reactant and water with a supported heteropolyacid catalyst at a temperature of at least 170 °C, wherein the process is initiated using a start-up procedure comprising the following steps: (i) heating the supported heteropolyacid catalyst to a temperature of at least 220 °C; (ii) maintaining the heat-treated supported heteropolyacid catalyst of step (i) at a temperature of at least 220 °C for a time sufficient to remove bound water from the heteropolyacid component of the supported heteropolyacid catalyst; (iii) under an anhydrous atmosphere, reducing the temperature of the heat-treated supported heteropolyacid catalyst of step (ii) to a temperature below 220 °C; and (iv) contacting the supported heteropolyacid catalyst of step (iii) with the reactant feedstream at a temperature of at least 170 °C. |