Feedstock change is hot and poppin’

A year that raised the public’s awareness of oil price trends, global warming, and other environmental sustainability issues also may prove to have been a turning point for the chemical industry. In 2005, the outlines of a substantially different industry, shifting gradually from petroleum-based feedstocks to renewable resources, gained clarity amid talk of a new generation of biorefineries and other initiatives involving new products, processes and partnerships.

Some of the news was about progress that already has been made by companies and consortia which, often with help from U.S. government grants, are exploring new pathways from plants, crop oils, and biomass waste to basic building blocks, chemical intermediates and fuels. Much of the buzz came from executives’ ambitious projections about the potential technological leaps, although there were also reminders that economic hurdles could slow change.

Growing momentum
DuPont, Wilmington, Del., was a leader in last year’s consciousness-raising. In a November briefing, Thomas M. Connelly, chief science and technology officer, pledged a 30% acceleration in science-based innovation, and cited bio-based materials as “the right science at the right time.” Components of DuPont’s bio-based materials pipeline have an estimated net present value exceeding $3 billion, he said.

The company has a joint venture with Tate & Lyle to build a $100-million plant at Loudon, Tenn., that will use corn to produce 1,3 propanediol (PDO) (see CP, October, p. 11). This building block, which DuPont has trademarked Bio-PDO, is a key ingredient in its Sorona polymer. The plant (Figure 1) is expected to start up in mid-2006. DuPont also said in November that it would invest $55 million to expand its Sorona plant at Lenoir County, N.C.

PDO plant

Figure 1. A 100-million-lb/yr-capacity 1,3 propanediol plant should start up mid-year in Loudon, Tenn.

Sorona is now made from petroleum-based PDO. The company estimates that production of Bio-PDO from corn will consume 30% to 40% less energy. “The corn fields of today will be the oilfields of the future,” said Tate & Lyle chief executive Iain Ferguson.

DuPont’s growing interest in bio-based feedstocks was also accentuated by the announcement of progress in another of its partnerships —  a consortium behind a $38-million project to develop an integrated biorefinery that will convert corn and other biomass into sugars for production of fuel ethanol as well as Bio-PDO and other chemicals. The consortium, which includes Diversa, Deere & Co., the National Renewable Energy Laboratory, and Michigan State University, backed by U.S. Dept. of Energy (DOE) funding, aims to demonstrate the feasibility of a biorefinery by the end of 2007.

Diversa, San Diego, Calif., announced in July that it had delivered a set of candidate enzymes that exceed DOE’s initial performance targets. Diversa says these enzymatic “cocktails” can break down a variety of crude plant materials — potentially including switchgrass, wood and corn stover as well as corn — into sugars ready for fermentation.

The biorefinery
“I like to think of this as very similar to an oil refinery, taking a very crude material, breaking it down into its smallest components and then making multiple business products out of it,” says Patrick McCroskey, Diversa’s vice president of business development.

Many facilities are already described as biorefineries, but this “integrated biorefinery” is different because it represents integration on so many different levels, McCroskey says. It requires the combination of biological, chemical and other expertise. It envisions multiple inflows of feedstocks and multiple outputs of fuels and other products. It recognizes the need to match modified cocktails of high-performing enzymes with different feedstocks and fermentation suited to different products. Perhaps most importantly, it recognizes the need to combine technologies in a way that meets business imperatives.

Conversion of lignocellulosic biomass into its component sugars is already technically feasible, says Mark Burk, Diversa’s senior vice president of chemical and industrial R&D. But the cost of conversion is too high, especially when one of the outputs is relatively low-cost ethanol. “It’s going to take a step change in the activity of the enzymes in order to get to where we need to be for economic viability.”

For Diversa, which also has biotech collaborations with other chemical companies including Syngenta, DSM, Cargill, and BASF, bio-based products have become a focus area, says McCroskey. But the speed with which the DuPont consortium has progressed should not imply that the path ahead is easy, he cautions, adding that government funding — which has averaged $100 million to $300 million annually for bio-based research in recent years — will still be necessary perhaps for a decade.

Chemical companies will face their own challenges, including the “dramatically different” processing that may be needed when a fermentation paradigm replaces a continuous production paradigm, McCroskey says. One key to success will be continued smart partnering between chemical companies and enzyme makers, so that the right, cost-effective technologies are developed in tandem. He is optimistic about the success of the DuPont-led consortium: “We may not be the first biorefinery, but we’ll be the first one that can make money.”