Hydrogenation of carbon dioxide for methanol production

Abstract

A process for the hydrogenation of CO2 to methanol with a capacity of 10 kt/y methanol is designed in a systematic way. The challenge will be to obtain a process with a high net CO2 conversion. From initially four conceptual designs the most feasible is selected and designed in more detail. The feeds are purified, heated to 250 °C and fed to a fluidized bed membrane reactor equipped with a Cu/ZnO/Al2O3 catalyst. Zeolite membranes mainly remove the methanol and shift the equilibrium reaction towards methanol. A yield of 25 % per pass is obtained. The permeate and the water-methanol mixture from the phase separator is finally separated in a distillation column. In the final design 15.4 kt/y of carbon dioxide is needed in order to produce 10 kt/y methanol. The net CO2 reduction is about 2/3, which is significant. The process is technical but currently not economically feasible.