Experimental investigations and model-based optimization of CZZ/H-FER 20 bed composition for the direct synthesis of DME from CO2-rich syngas

Experimental kinetics studies and model-based optimization were performed for the direct synthesis of dimethyl ether (DME) in a wide range of process conditions, including various CuO/ZnO/ZrO2:H-FER 20 bed compositions. This,...

Direct catalytic production of dimethyl ether from CO and CO2: A review

Dimethyl ether (DME) is a synthetically produced alternative fuel to diesel-based fuel and could be used in ignition diesel engines due to increasing energy demand. DME is considered extremely clean transportation and green fuel because it has a high cetane number (around 60), low boiling point (−25 °C), and high oxygen amount (35 wt%) which allow fast evaporation and higher combustion quality (smoke-free operation and 90% fewer NOx emissions) than other alternative CO2-based fuels. DME can be synthesized from various routes such as coal, petroleum, and bio-based material (i.e., biomass and bio-oil). Dimethyl ether can be produced from CO2 to prevent greenhouse gas emissions. This review aims to summarize recent progress in the field of innovative catalysts for the direct synthesis of dimethyl ether from syngas (CO+H2) and operating conditions. The problems of this process have been raised based on the yield and selectivity of dimethyl ether. However, regardless of how syngas is produced, the estimated total capital and operating costs in the industrial process depend on the type of reactor and the separation method.

Process Simulation and Environmental Aspects of Dimethyl Ether Production from Digestate-Derived Syngas

The production of dimethyl ether from renewables or waste is a promising strategy to push towards a sustainable energy transition of alternative eco-friendly diesel fuel. In this work, we simulate the synthesis of dimethyl ether from a syngas (a mixture of CO, CO2 and H2) produced from gasification of digestate. In particular, a thermodynamic analysis was performed to individuate the best process conditions and syngas conditioning processes to maximize yield to dimethyl etehr (DME). Process simulation was carried out by ChemCAD software, and it was particularly focused on the effect of process conditions of both water gas shift and CO2 absorption by Selexol® on the syngas composition, with a direct influence on DME productivity. The final best flowsheet and the best process conditions were evaluated in terms of CO2 equivalent emissions. Results show direct DME synthesis global yield was higher without the WGS section and with a carbon capture equal to 85%. The final environmental impact was found equal to −113 kgCO2/GJ, demonstrating that DME synthesis from digestate may be considered as a suitable strategy for carbon dioxide recycling.