(487ab) Methanol and DME Synthesis Process for CO2 Mitigation

Both methanol and DME processes produce a lot of CO2 during the operation. A key way to mitigate CO2 in the aspect of process yield is to utilize abundant hydrogen from the methane stream reforming. For that, the reverse water gas shift reaction catalysts should be developed. The thermodynamics indicate that the reverse water shift reaction catalysts should be robust under the reductive conditions of the temperature higher than 600 oC. Until now, ZnAl2O4 catalysts have been best for the reverse water shift reaction in the composition aspects, although other catalysts such as ZnZrO3 and ZnO-TiO2 were attempted. Additionally, highly active methanol synthesis catalysts were developed by enhancing the crystallinity of hydroxy carbonate precusors during the Cu-Zn-Al-M catalysts preparation. It was found that the relative rate of methanol synthesis/methanol dehydration was a key for the direct DME synthesis. Alumina catalysts of hexagonal crystallites showed the best activity among the tested alumina catalysts. Finally, the processes to mitigate CO2 were suggested with mass and heat balances.