In this scientific study featured in Science (2023), a novel procedure for creating CDTO (Carbon-Doped Metal Oxide) nanofilms on porous substrates with various morphologies is outlined. Two distinct substrates are depicted: (A) a flat sheet AAO support and (B) an α-aluminum ceramic hollow fiber support.
The separation of molecules plays a crucial role in the production of essential goods. In industries like petroleum refining, the separation of hydrocarbons from crude oil into products like gasoline, diesel, and lubricants relies on molecular size, shape, and weight sorting. Similarly, in the pharmaceutical sector, the purification of active drug ingredients involves the separation of drug molecules from enzymes, solutions, and other components used in their manufacture.
These separation processes consume a significant amount of energy, accounting for approximately half of U.S. industrial energy consumption. Traditional methods rely on energy-intensive heating and cooling, making them inefficient.
As chemical and biological engineers, our recent research, published in Science, introduces a groundbreaking membrane technology featuring nanopores capable of swiftly and precisely separating a diverse range of molecules even under harsh industrial conditions.
Membranes are physical barriers that can selectively separate molecules based on size or other properties like charge or polarity, akin to a sieve. These synthetic barriers reduce the energy cost of separating molecules in industrially significant mixtures compared to traditional methods.
However, existing membranes, including those employed in large-scale seawater desalination, suffer from instability at high temperatures and in the presence of organic solvents, limiting their applicability in various industrial separations.
To address these limitations, we developed a novel inorganic material called carbon-doped metal oxide, capable of separating organic molecules smaller than one nanometer in diameter. Using a technique inspired by semiconductor manufacturing known as molecular layer deposition, we synthesized thin films containing nanopores that can be precisely tailored to separate molecules ranging from 0.6 to 1.2 nanometers in diameter.
One key feature of our membrane is its robustness, as it can withstand harsh conditions, remaining stable up to 284°F (140°C) and pressures up to 30 atmospheres even in the presence of organic solvents. This stability is crucial for industrial processes that can significantly reduce energy consumption when operated at high temperatures.
To illustrate its effectiveness, we utilized our membrane in the molecule separation step of pesticide boscalid production. By customizing the pore sizes to match the molecules in the mixture, we successfully separated reactants, products, and catalysts individually at 194°F (90°C), eliminating the need to lower the temperature during the separation process. This substantial energy savings can reduce the carbon footprint of industrial processes.
We believe that our membrane has the potential to revolutionize various industrial processes, particularly those involving harsh conditions where conventional membranes falter. Furthermore, we are confident in its scalability, which could open doors to new applications for researchers and manufacturers.
For more details, refer to the research article: “Carbon-doped metal oxide interfacial nanofilms for ultrafast and precise separation of molecules” by Bratin Sengupta et al., published in Science (2023). [DOI: 10.1126/science.adh2404]
Source: The Conversation