new findings

Rice research team's study keeps CO2-to-fuel devices running 50 times longer

Ahmad Elgazzar, Haotian Wang and Shaoyun Hao were members of a Rice University team that recently published findings on how acid bubbling can improve CO2 reduction systems. Photo courtesy Rice.

In a new study published in the journal Science, a team of Rice University researchers shared findings on how acid bubbles can improve the stability of electrochemical devices that convert carbon dioxide into useful fuels and chemicals.

The team led by Rice associate professor Hoatian Wang addressed an issue in the performance and stability of CO2 reduction systems. The gas flow channels in the systems often clog due to salt buildup, reducing efficiency and causing the devices to fail prematurely after about 80 hours of operation.

“Salt precipitation blocks CO2 transport and floods the gas diffusion electrode, which leads to performance failure,” Wang said in a news release. “This typically happens within a few hundred hours, which is far from commercial viability.”

By using an acid-humidified CO2 technique, the team was able to extend the operational life of a CO2 reduction system more than 50-fold, demonstrating more than 4,500 hours of stable operation in a scaled-up reactor.

The Rice team made a simple swap with a significant impact. Instead of using water to humidify the CO2 gas input into the reactor, the team bubbled the gas through an acid solution such as hydrochloric, formic or acetic acid. This process made more soluble salt formations that did not crystallize or block the channels.

The process has major implications for an emerging green technology known as electrochemical CO2 reduction, or CO2RR, that transforms climate-warming CO2 into products like carbon monoxide, ethylene, or alcohols. The products can be further refined into fuels or feedstocks.

“Using the traditional method of water-humidified CO2 could lead to salt formation in the cathode gas flow channels,” Shaoyun Hao, postdoctoral research associate in chemical and biomolecular engineering at Rice and co-first author, explained in the news release. “We hypothesized — and confirmed — that acid vapor could dissolve the salt and convert the low solubility KHCO3 into salt with higher solubility, thus shifting the solubility balance just enough to avoid clogging without affecting catalyst performance.”

The Rice team believes the work can lead to more scalable CO2 electrolyzers, which is vital if the technology is to be deployed at industrial scales as part of carbon capture and utilization strategies. Since the approach itself is relatively simple, it could lead to a more cost-effective and efficient solution. It also worked well with multiple catalyst types, including zinc oxide, copper oxide and bismuth oxide, which are allo used to target different CO2RR products.

“Our method addresses a long-standing obstacle with a low-cost, easily implementable solution,” Ahmad Elgazzar, co-first author and graduate student in chemical and biomolecular engineering at Rice, added in the release. “It’s a step toward making carbon utilization technologies more commercially viable and more sustainable.”

A team led by Wang and in collaboration with researchers from the University of Houston also shared findings on salt precipitation buildup and CO2RR in a recent edition of the journal Nature Energy. Read more here.

Trending News

 

A View From HETI

Lydian Energy has secured financing for three battery storage system projects in Texas. Photo via Getty Images.

The Electricity Reliability Council of Texas’ grid will get a boost courtesy of Lydian Energy.

The D.C.-based company announced the successful financial close of its first institutional project financing totaling $233 million, backed by ING Group and KeyBank. The financing will support three battery energy storage system (BESS) projects in Texas.

Lydian is an independent power producer that specializes in the development, construction and operation of utility-scale solar and battery energy storage projects. The company reports that it plans to add 550 megawatts of energy—which can power approximately 412,500 homes—to the Texas grid administered by ERCOT.

“This financing marks an important step forward as we continue executing on our vision to scale transformative battery storage projects that meet the evolving energy needs of the communities we serve,” Emre Ersenkal, CEO at Lydian Energy, said in a news release.

The projects include:

Pintail 

  • Located in San Patricio county
  • 200 megawatts
  • Backed by ING

Crane

  • Located in Crane county
  • 200 megawatts
  • Backed by ING

Headcamp

  • Located in Pecos county
  • 150 megawatts
  • Backed by KeyBank

ING served as the lender for Pintail and Crane projects valued at a combined total of approximately $139 million.

KeyBank provided a $94 million financing package for the Headcamp project. KeyBanc Capital Markets also structured the financing package for Headcamp.

The three projects are being developed under Excelsior Energy Capital’s Fund II. Lydian’s current portfolio comprises 20 solar and storage projects, totaling 4.7 gigawatts of capacity.

“Our support of Lydian’s portfolio reflects ING’s focus on identifying strategic funding opportunities that align with the accelerating demand for sustainable power,” Sven Wellock, managing director and head of energy–renewables and power at ING, said in the release. “Battery storage plays a central role in supporting grid resilience, and we’re pleased to back a platform with strong fundamentals and a clear execution path.”

The facilities are expected to be placed in service by Q4 2025. Lydian is also pursuing additional financing for further projects, which are expected to commence construction by the end of 2025.

“These financings represent more than capital – they reflect the strong demand for reliable energy infrastructure in high-growth U.S. markets,” Anne Marie Denman, co-founding partner at Excelsior Energy Capital and chair of the board at Lydian Energy, added in the news release. “We’re proud to stand behind Lydian’s talented team as they deliver on the promise of battery storage with bankable projects, proven partners, and disciplined execution. In the midst of a lot of noise, these financings are a reminder that capital flows where infrastructure is satisfying fundamental needs of our society – in this case, the need for reliable, sustainable, domestic, and affordable energy.”

Trending News