Plastic from Algae Biomass: Roads to Algal Profitability

PopMech
Algae are used to produce a wide range of high value products: nutraceuticals, cosmetics, animal feed, etc. Now algal biomass can be turned into plastics -- substituting for petro-feedstocks. Growing algae for biomass should be easier than growing algae to produce bio-oils, therefore a quicker road to profits for algal growers.

By year's end, an Indiana company says it will be making plastic from algae, substituting up to half of the material normally derived from fossil fuels with biomass from the aquatic plants, and selling the product to manufacturers.

As the bioplastics industry surges, a search for alternative feedstocks led Cereplast CEO Frederic Scheer and his colleagues to algae, which he says is close enough to the starches the company already turns into plastics—like corn, wheat and tapioca—to go commercial after just 18 months of R&D. There's just one hitch: getting enough of the green stuff to make it in quantity. Given a big enough source of algae, Scheer says, "we could have introduced this product probably last year."

Algae has long been hailed by many as the best hope for an alternative to fossil and food-based fuels, but difficulties growing and processing it cheaply have kept it just over the green horizon for decades. The myriad companies running at algal biofuels today, for example, must first find and cultivate a precise strain of algae from among thousands, harvest and dry the stuff, and then somehow extract oil from the plant on a cost-competitive basis with now very cheap crude.

But Scheer and his colleagues are betting not only that someone will soon crack algae once and for all, but that, once they do, they'll be stuck with a green mountain of biomass left over after the algae's oil has been extracted and turned into the diesel or jet fuel of tomorrow. Today, that biomass is fed to cattle, among other things. Tomorrow, Scheer hopes, it will be an integral part of the trillion-dollar industry that is plastic.

At the moment, Scheer says, his team has succeeded in displacing up to 35 percent of the petroleum in traditional plastics with algae. By product launch later this year, he's hoping that figure will be closer to 50 percent. But, like his comrades in the algae-oil business, the trouble hasn't been so much the science, but the supply of algae to his lab.

...Scheer stresses that his team's main goal is to derive a monomer—the building block of the polymers most of us call plastics—entirely from algae biomass. Such a breakthrough, combined with enough cast-aside plant matter to sustain it, and possibly some of the plant's oil, would provide for a plastic completely free of fossil fuels. If such plastics became prevalent on a large scale, they could theoretically present something of an ecological holy grail, with a gyre full of bioplastic representing something closer to fish food than deathtrap.

"Creating that monomer from the algae, we'd be able to create other polymers and end up really creating a whole chemistry around algae biomass, and this is probably the ultimate purpose of the work that we're doing here," Scheer says, estimating that such results are at least three to five years away. _PM

Some critics of algae suppose that if algal fuels cannot completely displace all fossil fuels by next week, that algae is worthless. But no one expects algal bio-oils to become competitive with fossil fuels for another ten years. Algal biomass-to-fuels may become competitive a bit sooner. Some microbial fuels besides micro-algae may actually become competitive within 5 years, but it is difficult to beat algae in terms of rapid growth under the right conditions. We'll see.