Producing Syngas From CO2 And Sunlight With Direct Air Capture

March 21, 2025 by Maya Posch 17 Comments

The prototype DACCU device for producing syngas from air. (Credit: Sayan Kar, University of Cambridge)

There is more carbon dioxide (CO₂) in the atmosphere these days than ever before in human history, and while it would be marvelous to use these carbon atoms for something more useful, capturing CO₂ directly from the air isn’t that easy. After capturing it would also be great if you could do something more with it than stuff it into a big hole. Something like producing syngas (CO + H₂) for example, as demonstrated by researchers at the University of Cambridge.

Among the improvements claimed in the paper as published in Nature Energy for this direct air capture and utilization (DACCU) approach are that it does not require pure CO₂ feedstock, but will adsorb it directly from the air passing over a bed of solid silica-amine. After adsorption, the CO₂ can be released again by exposure to concentrated light. Following this the conversion to syngas is accomplished by passing it over a second bed consisting of silica/alumina-titania-cobalt bis(terpyridine), that acts as a photocatalyst.

The envisioned usage scenario would be CO2 adsorption during the night, with concentrated solar power releasing it the day with subsequent production of syngas. Inlet air would be passed only over the adsorption section before switching the inlet off during the syngas generating phase. As a lab proof-of-concept it seems to work well, with outlet air stripped from virtually all CO₂ and very high conversion ratio from CO₂ to syngas.

Syngas has historically been used as a replacement for gasoline, but is also used as a source of hydrogen (e.g. steam reformation (SMR) of natural gas) where it’s used for reduction of iron ore, as well as the production of methanol as a precursor to many industrial processes. Whether this DACCU approach provides a viable alternative to SMR and other existing technologies will become clear once this technology moves from the lab into the real world.

Thanks to [Dan] for the tip.

Solar Energy Plant Creates Fuel

June 29, 2024 by Al Williams 24 Comments

Normally, when you think of solar power, you think about photovoltaic cells or using the sun to generate steam. But engineers at Synhelion — a spin off from ETH Zurich — had a crazy idea. Could you reverse combustion and change waste products back into fuel? The answer is yes if you can use the sun to turn things up to 1,500°C.

The input is water, carbon dioxide, and methane into syngas. The pilot plant in Germany is set to begin operations using a thermal storage device to allow the plant to operate around the clock. The new plant is slated to produce several thousand liters of fuel a year. Future plants will produce more, and they are targeting a cost of $1 per liter of fuel. The pilot plant has a 20-meter-tall tower and around 1,500 square meters of mirrors, producing 600 kW of output. The hexagonal mirrors are very thin, and the plant uses drones to aim the mirrors quickly compared to other methods.

Syngas shows up a lot lately. Getting to 1,500 degrees is a big ask, although we’ve seen ETH Zurich get to 1,000 using solar.

Fuel Cell Turns PET And Carbon Dioxide Into Useful Chemicals

June 21, 2023 by Al Williams 17 Comments

The University of Cambridge has a novel fuel cell design that can grab CO₂ from the atmosphere or industrial processes and, combined with waste PET plastic, provides syngas and glycolic acid, a product used in some cosmetics. You can read about the device in a recent paper.

The strange juxtaposition of CO₂ and PET is no accident. The processes work together with solar energy. There is no external voltage required, but the cell operates as a photocell to produce electricity from the solar energy. Removing both CO₂ and waste plastic from the environment is a good thing.

Syngas is hydrogen and carbon monoxide and finds use in producing methanol and ammonia. It also will work as a fuel that can replace gasoline when gasoline isn’t available. It has a few other uses, like reducing iron ore to sponge iron and even converting methanol to gasoline.

The technology has a ways to go to operate at scale, and we doubt this will ever be a consumer item since you are unlikely to need syngas or glycolic acid in your home or vehicle. But it still is a promising technique to reduce both greenhouse gas and plastic waste in one swoop.

We’ve looked at other ways to grab carbon dioxide and make it useful. If you want to make your own syngas, there are other ways to do it.

Is GEK A Modern-day Mr. Fusion?

March 4, 2010 by Mike Szczys 42 Comments

[Nanomonkey] spent the weekend building generators that run off of syngas. All Powers Lab produces Gasifier Experimenter Kits to convert raw material to energy. The kits use Gasification to make a “natural gas like” fuel from materials such as wood chips, walnut shells, construction debris or agricultural waste.

So is this the Mr. Fusion that powered the DeLorean? This Honda fitted with a GEK sure makes it look that way. But all joking aside, this looks like a great way to turn waste in heat or electricity. There’s tons of info on the site to dig through. The controllers are open source which would make it easier to interface with the Google PowerMeter when the system is used as a generator.