INSIGHT: US Viridis proving new tech that converts ethanol to etac

HOUSTON (ICIS)–The successful startup of Viridis Chemical’s new commercial-scale ethyl acetate (etac) plant is proving that its new technology works, opening the way to develop additional products using the process.

• Viridis started commercial operations at the end of December 2022 at its plant at Columbus, Nebraska, with a capacity of 52,000 tonnes/year, by far the largest etac plant in the US
• Viridis expects the process will be competitive with the predominant route to making etac because it is simpler and more efficient
• The surge in prices for natural gas and naphtha could give Viridis’s process a cost advantage in regions without ready access to low-cost feedstock

PRODUCTION ROUTE
Viridis’s process is unique because its main stock is ethanol, which it converts into etac and byproduct hydrogen with a catalyst in a single step.

That contrasts with the typical production route for etac, which is made by combining acetic acid with ethanol through a Fischer esterification reaction. According to ICIS, the reaction is relatively slow and does not have the highest yields. Moreover, the resulting etac is mixed with water, ethanol and acetic acid, making it difficult to separate the chemicals.

All of this adds to operating and capital costs, according to ICIS.

By contrast, Viridis converts virtually all of the feedstock through a closed loop process, which loops back any unreacted ethanol into the reactor, according to the company.

Moreover, the process produces water, hydrogen and some other co-products that are easily separated, according to Viridis.

In the end, the company’s material is competitive with traditional etac, even though ethanol typically costs more than acetic acid. Viridis can compete without a so-called green premium that some customers are willing to pay to obtain chemicals made of renewable materials.

“We compare very favourably,” said Carl Rush, Viridis co-founder and CEO. “Our cost is primarily our raw material cost. The production cost is not that high.”

MARKETING STRATEGY
Right now, Viridis is easing into the market, Rush said.

Rush said the plant’s etac is among the purest – if not the purest – material on the market. It is urethane grade, and Viridis’s marketing partner, HELM, is targeting all of the typical applications for etac, such as paints, coatings, adhesives, pharmaceuticals and cosmetics.

Although Viridis’s etac is competitive by itself, the company still wants to use the renewable credentials of its etac to attract customers. Rush said the greenhouse gas emissions associated with its etac production are 80% lower than the typical route.

In the past, interest in products made of renewable or recycled materials was limited to mostly producers of consumer goods with well-known brands. Recently, a greater variety of customers are interested in such products.

“Those companies all have goals of how they are going to reduce their carbon intensity,” Rush said. “Anything they can do is viewed as favourable as long as it’s price competitive.”

In particular, European customers are attracted to the product’s low-carbon credentials, Rush said.

Viridis shipped little material to Europe this year, but that should change as the economy improves and as the company continues to ramp up production. The plant was initially designed to ship a significant share of its output to Europe.

VIRIDIS PLANS TO CONVERT HYDROGEN TO AMMONIA
Viridis also plans to convert its hydrogen into ammonia instead of burning it as fuel.

The resulting fertilizer could be used in the cornfields that supply Viridis with ethanol.

NEW PRODUCT DEVELOPMENT
With the successful startup of the plant, Viridis is reviewing ways to use its process technology to make other chemicals.

“Going to the next product is a minor modification from what we are doing today. It’s not re-inventing the wheel,” Rush said.

“We’ve got a pretty aggressive rollout plan of our technology platform over the next couple of years for new products,” he said. “We think we have a very strong green chemicals platform.”

There could be an announcement before the end of 2023, he said.

HISTORY OF PLANT AND TECHNOLOGY
The history of the plant goes back to 2008, with the founding of Greenyug, the company that would go on to file a patent to produce etac by using only ethanol and a catalyst.

Construction on a commercial-scale plant was planned to start in 2017. In mid-2019, Greenyug subsidiary Prairie Catalytic had managed to produce on-spec material at the plant.

The plant shut down later in 2019 as the company was going through an ownership change.

Ultimately, Viridis would purchase the plant, after lining up equity capital commitments from EIV Capital and IFG Management.

Earlier this year, it won the ICIS 2023 Best Product Innovation Award under small- to -medium business category.

Insight article by Al Greenwood

Thumbnail shows corn, the feedstock used to make the ethanol that Viridis converts into etac. Image by Shutterstock.