Cleaner production of methanol from carbon dioxide over copper and iron supported MCM-41 catalysts using innovative integrated magnetic field-packed bed reactor

Abstract

In this research, an external magnetic field has been employed to a catalytic packed bed reactor in order to improve the performance of copper and iron supported MCM-41 catalysts in carbon dioxide utilization through hydrogenation reaction. The result showed that magnetic field significantly improved carbon dioxide conversion at all reaction temperatures. The highest carbon dioxide conversion was obtained over 10(Cu)-10(Fe)/MCM-41 catalyst with magnetic flux density of –27.7 mT in north-to-south (N–S) direction which was 1.8 times higher than that of without magnetic field. In addition, the methanol space time yield was 1.5 times higher than that of without magnetic field and therefore, the lowest apparent activation energy (34.5 kJ/mol) was achieved. As a result, this integrated magnetic field-packed bed reactor could significantly reduce the operating temperature by 32.9 oC, 33.8 oC, and 57.7 oC over 10(Cu)/MCM-41, 10(Fe)/MCM-41, and 10(Fe)-10(Cu)/MCM-41 catalysts, respectively compared to those without magnetic field at the reaction temperature of 260 oC. With 10(Fe)-10(Cu)/MCM-41 catalyst, magnetic field could save electric energy costs of 2,074–48,373 $/a with payback periods of 4.7–0.2 a at reaction temperatures of 180–260 ºC, respectively based on CO2 conversion of 100 kg/h. This outstanding performance could be attributed to the fact that magnetic field facilitated carbon dioxide adsorption on the magnetized catalyst surfaces. This led to the advantages of a heterogeneously catalyzed reaction including the enhancement of carbon dioxide utilization and methanol formation, the decrease of operating temperature, and the simultaneous decrease of carbon dioxide emission by means of energy-efficient process modification.