New Water-Conducting Membrane Could Convert CO2 to Fuel

Researchers have developed a water-conducting membrane to convert carbon dioxide into fuel effectively.

Methanol is an efficient chemical that could serve as fuel in various machines. Meanwhile, Carbon dioxide is a greenhouse gas — an unwanted byproduct of many industrial processes.

So, it only makes sense to convert the greenhouse gas into useful fuel. But there’s a problem.

The chemical reaction to convert CO2 into methanol also produces a lot of water. And this could severely restrict the continued reaction. As a result, researchers could only generate a limited amount of methanol from carbon dioxide.

To address this issue, a team of chemical engineers from Rensselaer Polytechnic Institute created a separation membrane. That way, they could filter out the water as the reaction happened without losing the gas molecules.

Here’s how it works.

Using a Water-Conducting Membrane to Convert CO2 to Fuel

First, the Rensselaer Polytechnic team assembled a membrane that consists of sodium ions and zeolite crystals. Thanks to these compounds and the water-conducting nanochannels, the layer could allow the passage of water without losing gas molecules.

Lead author of the study and a member of the Center for Biotechnology and Interdisciplinary Studies (CBIS) at Rensselaer, Miao Yu explained:

“The sodium can actually regulate, or tune, gas permeation. It’s like the sodium ions are standing at the gate and only allow water to go through. When the inert gas comes in, the ions will block the gas.”

Previous versions of the membrane were susceptible to defects that would allow gas molecules to leak out. However, Yu and colleagues were able to eliminate those defects by optimizing the assembly of crystals.

“When we can remove the water, the equilibrium shifts, which means more CO2 will be converted, and more methanol will be produced,” said Huazheng Li, a postdoctoral researcher at Rensselaer and first author on the paper.

Now, the researchers are working on a scalable process. They also intend to launch a startup that would produce high purity methanol using the water-conducting membrane.