Catalytic methane combustion in plate-type microreactors with different channel configurations: An experimental study

Process concepts and analysis for co-removing methane and carbon dioxide from the atmosphere

Methane is the second largest contributor to global warming after CO2, and it is hard to abate due to its low concentration in the emission sources and in the atmosphere. However, removing methane from the atmosphere will accelerate achieving net-zero targets, since its global warming potential is 28 over a 100-year period. This work presents first-of-its-kind process concepts for co-removal of methane and CO2 that combines the catalytic conversion of methane step (thermal/photo-catalytic) with CO2 capture. Proposed processes have been analyzed for streams with lean methane concentrations, which are non-fossil emissions originating in the agricultural sector or natural emissions from wetlands. If the proposed processes can overcome challenges in catalyst/material design to convert methane at low concentrations, they have the potential to remove more than 40% of anthropogenic and natural methane emissions from the atmosphere at a lower energy penalty than the state-of-the-art technologies for direct air capture of CO2.

Towards Heterogeneous Catalysis: A Review on Recent Advances of Depositing Nanocatalysts in Continuous-Flow Microreactors

As a promising technology, microreactors have been regarded as a potential candidate for heterogeneous catalytic reactions as they inherently allow the superior advantages of precise flow control, efficient reactant transfer, flexible operation, etc. However, the wide market penetration of microreactors is still facing severe challenges. One of the most important reasons is the preparation of a high-performance catalytic layer in the microreactor because it can directly influence the catalytic activity and stability the reactor and thus the deployment the microreactor technology. Hence, significant progress in depositing nanocatalysts in microreactors has been made in the past decades. Herein, the methods, principles, recent advances, and challenges in the preparation of the catalyst layer in microreactors were presented. A general description of the physicochemical processes of heterogeneous catalytic reactions in microreactors were first introduced. Then, recent advances in catalyst layer preparation in microreactors were systematically summarized. Particular attention was focused on the most common sol-gel method and its latest developments. Some new strategies proposed recently, including bio-inspired electroless deposition and layer-by-layer self-assembly, were also comprehensively discussed. The remaining challenges and future directions of preparing the catalytic layer in microreactors with high performance and low cost were highlighted.