Optimizing hierarchical membrane/catalyst systems for oxidative coupling of methane using additive manufacturing.

Area of Science:

• Chemical Engineering
• Materials Science
• Catalysis

Background:

• Conventional reactors for methane oxidative coupling suffer from low selectivity due to parasitic gas-phase reactions.
• Existing membrane/catalyst systems face challenges with low conversion rates, high costs, and difficulties in optimizing membrane and catalyst properties.
• Oxygen introduction via a membrane can improve selectivity by avoiding gas-phase reactions.

Purpose of the Study:

• To develop an additive manufacturing process for fabricating optimized hollow-fibre membrane/catalyst systems for methane oxidative coupling.
• To address limitations of low volumetric conversion rates, high capital costs, and co-design challenges in membrane/catalyst systems.
• To demonstrate the critical role of 'rate matching' between oxygen flux and methane activation for enhanced performance.

Main Methods:

• A dual-layer additive manufacturing process based on phase inversion was developed.
• A hollow-fibre membrane/catalyst system was designed, fabricated, and optimized.
• A case study utilized BaCe0.8Gd0.2O3-δ for both catalyst and separation layers.

Main Results:

• The additive manufacturing process enabled co-design of membrane thickness and catalyst surface area.
• 'Rate matching' between oxygen transport flux and methane activation was achieved.
• The developed membrane/catalyst system significantly outperformed conventional reactor designs.

Conclusions:

• Additive manufacturing offers a viable solution for overcoming limitations in membrane/catalyst system design and fabrication.
• Co-design and 'rate matching' are crucial for maximizing the efficiency of methane oxidative coupling.
• This approach provides a pathway for developing high-performance catalytic systems for methane conversion.