World’s biggest spandex maker is going biobased

Hyosung, the world’s largest maker of spandex fibers, plans to spend $1 billion on a site in Vietnam that will use Genomatica’s fermentation technology to convert sugar into 1,4-butanediol (BDO), a spandex precursor that’s typically made from coal or natural gas. Hyosung plans to produce 50,000 metric tons (t) of biobased BDO per year by 2026 and 200,000 t annually by 2035.

In addition to spandex, BDO is used to make polybutylene terephthalate and other plastics. Most BDO is produced in China, where many plants use coal as a starting material.

Hyosung’s facilities would eventually be much larger than others using the same technology. Qore, a joint venture between Cargill and Helm, is building a $300 million factory in Iowa that will be able to produce 65,000 t of BDO when it opens in 2026. And Novamont has been using Genomatica’s technology at a 30,000-metric-ton-per-year plant in Italy since 2016.

Genomatica claims that its BDO process generates 90% fewer greenhouse gases than coal-based processes. The emission reduction is more modest when compared with that of natural gas–based routes, which are more common outside China. Novamont has said its process cuts the carbon footprint of BDO by 56%.

BASF announced last month that it is trying to sell its stake in a coal-based BDO plant in China’s Xinjiang region after reports linked the co-owner of the plant to abuses of the Uyghur ethnic group. But BASF also cited overcapacity in the BDO market and the high carbon footprint of BDO made from coal as reasons for the sale. In 2021, global capacity for BDO was nearly 4 million t, but demand was closer to 2.5 million t, according to S&P Global Commodity Insights.

Given the oversupply, both BASF and Hyosung say they’re focused on the growing segment of consumers demanding sustainably produced clothing. In 2023, BASF announced that it would buy biobased BDO from Qore. In a press release, Hyosung chairman Hyun-Joon Cho says biobased materials will be a core part of the company’s business in the coming years.

Fermentation isn’t the cheapest way to make BDO, but Genomatica CEO Christophe Schilling says the growing number of biobased BDO plants is proof that the trend toward more-sustainable chemicals isn’t slowing down. “You’re going to start seeing more and more plants getting built,” he says. “The technology is improving every day.”