CONTINUOUS PROCESS FOR THE PREPARATION OF METHANOL BY HYDROGENATION OF CARBON DIOXIDE

摘要

The present invention pertains to a continuous process for the preparation of methanol by hydrogenation of carbon dioxide in the presence of a solid catalyst comprising the steps of (i) feeding a feed comprising carbon dioxide; and at least part of a first recycle gas stream comprising carbon dioxide and hydrogen,to a reactor, to obtain a gaseous feed with a hydrogen:carbon dioxide molar ratio of between 2-18 : 1; (ii) contacting said gaseous feed with a catalyst at a temperature of between200 and 300°C and a pressure of between 40 and 200 bar, thereby forming an outlet stream comprising methanol, water, carbon monoxide, carbon dioxide, and hydrogen; (iii) cooling the outlet stream; (iv) subjecting said outlet stream to a separation step, while optionally at least part of a second recycle gas stream is added to said outlet stream comprising methanol prior to and/or during said separation step, in which separation step methanol and water are separated from non-condensable components, thereby forming a methanol-comprising product stream and a first recycle gas stream; (v) stripping the methanol-comprising product stream using a hydrogen stream, thereby forming a purified methanol product stream and a second recycle gas stream; and (vi)feeding at least part of the first recycle gas stream to step (i) and at least part of the second recycle gas stream to steps (i) and/or (iv).