Highly Conductive Structured Catalytic Reactors for One-Step Synthesis of Dimethyl Ether

Area of Science:

• Chemical Engineering
• Catalysis
• Reaction Engineering

Background:

• Direct synthesis of dimethyl ether (DME) is crucial for sustainable energy solutions.
• Structured catalytic reactors offer potential advantages over traditional packed beds.
• Optimizing reactor design is key to enhancing DME synthesis efficiency.

Purpose of the Study:

• To compare structured catalytic reactors for direct DME synthesis.
• To evaluate the impact of catalyst structuring and reactor design on performance.
• To determine optimal conditions for high volumetric productivity.

Main Methods:

• Washcoating catalysts onto various substrates (FeCrAl, brass, aluminum) with different shapes (monoliths, foams).
• Comparing catalyst hold-up, thermal conductivity, and volumetric productivity.
• Analyzing CO conversion and selectivity under experimental conditions.

Main Results:

• Washcoating produced adherent, homogeneous catalyst layers irrespective of substrate.
• Substrate type and shape had minor effects on CO conversion and selectivity.
• Washcoated reactors showed lower catalyst inventory than packed-bed monoliths.
• Packed-bed monoliths resulted in a ~25% decrease in CO conversion.
• High catalyst hold-up in brass monoliths enabled near-isothermal operation.
• Achieved volumetric productivity of 0.20 L_DME/h·cm³ at 573 K.

Conclusions:

• Washcoating is an effective method for structuring catalysts in DME synthesis reactors.
• Reactor design and substrate properties have limited impact on intrinsic catalytic performance.
• Structured reactors, particularly washcoated ones, offer superior volumetric productivity and process control.